When we arrived at Gare du Nord station in Paris to get the Eurostar train back to London, I noticed terminals offering tax back to citizens of certain countries. To my surprise, I saw the UK flag on the terminal - and then started to think I'd perhaps made a mistake not keeping all receipts and attempting to get the tax back. Could we have ended up with a big refund if we'd kept all receipts? And is there a way to claim any tax refunds now we're home?

I have written twice to Yorkshire-General Life Assurance about an old pension, but both times, the letter has been returned with a note saying: 'Not known at this address'. The sum is hardly a fortune - but the firm appears determined not to pay out.

I was cold-called in August by Incrementum Funding and told shares in Paragon Time Trading would be an excellent investment. I was dubious, but after a number of calls I was persuaded to invest £6,000.

In 1993, we bought a timeshare, now controlled by the Cameron House Owners' Club. We have been asking since 2004 for this to be sold, and we paid all annual management fees until 2012, after which we returned our ownership certificate. Recently we received a demand for £3,010 with threats that debt collectors would be involved. We have serious medical conditions and cannot use the timeshare. It appears worthless, yet we are still harassed for payment.

Following a cold call, I received an email from the London Option Exchange about investing in fixed return options. The company stated it was registered with the Financial Conduct Authority, but gave me a false registration number. I phoned the regulator but it said it could do nothing, and I should phone the police. I contacted Action Fraud, but worry that it will either do nothing or be too slow, by which time people will have been defrauded.

I am writing about your article on Paragon Time Trading last Sunday. I was contacted by Daniel Knight of Incrementum Funding, who over a few days persuaded me to invest £6,000 in Paragon shares on the promise of an imminent dividend of £135, which did arrive. More calls followed and I parted with a further £9,000. (Yes, I know. How stupid).

Last year I invested with a binary options company called Bull Markets Solutions Limited. With my account in profit and holding almost £11,000, I tried to withdraw my money but nothing was forthcoming. I received an email from a separate company, Elite Business Solutions, informing me BMS was in liquidation and Elite had been appointed to recover clients' funds. It requested fees of £3,750 and then a further £1,500, which I paid, but recently it requested another £10,500, which I said I could not pay. Elite suggested I borrow the money, which I regard as dangerous.

My daughter and her husband loaned me £30k several years ago so I could improve and carry out essential work to my home. I asked if they could reduce the interest rate, but they refused and this caused friction between us. I have noisy neighbours from hell and am desperate to move.

T.K. writes: I have been in business as a hairdresser for 20 years at the same address, employing two part-time staff. The agreement between the landlord and myself is that electricity is included in my rent. I have now received a letter from debt collector Arvato, saying that I owe British Gas £20,038 for electricity. I have never even received a bill before, though the meter has been read regularly. Can you help?

I got into debt but found a reliable debt management company - Moneyplus. I reached a point where only about 18 monthly payments were left due, but meanwhile my two sons and I inherited some money which I invested. Half belonged to a son who is mentally ill. When this matured, Moneyplus took all the money without my knowledge and now wants me to set up another arrangement.

Ms P.H. writes: My adult son lives alone, but suffers with mental health issues. I was appointed to act for him in 2008 and his state benefits were paid into an account in my name, from which I paid his bills and allocated him £50 a week. Unknown to me, his community psychiatric nurse took over this task. I discovered this purely by chance. I have written to the Department for Work & Pensions and the local NHS mental health team, but without reply.

F.F. writes: I received a phone call from Sky Protect about renewing cover for our Sky TV system. The caller asked me to confirm my bank details, which I gave. I did not think any more about this until I found £249 had been taken from my account by Sky Protect Limited. As I normally pay by monthly direct debit, I phoned Sky and found that the caller was not from the official Sky Protect scheme. My bank says it cannot help as I had nothing in writing.

I went ahead with a property sale abroad, believing that clearing the draft would take about five days. But when I went to the branch with the draft, I was told it would take four to six weeks. This has left me with insufficient funds to buy our new home and the prospect of having nowhere to live.

One of Britain's biggest carbon credit investment cheats has been banned from acting as a company director for 12 years. Meanwhile, Israel's parliament, the Knesset, has taken the first steps towards a ban on binary options firms operating from the country.

My 95-year-old mother ordered a fitted chair from Westminster Recliners Limited on July 7, for delivery in August. The chair has still not arrived. We have tried to contact the firm several times but were fobbed off with a mobile number that does not work, or told we cannot speak to the manager. My mother has asked for the contract to be cancelled and her money refunded, but she has received neither the chair nor a refund.

We read with great interest your recent stories about FedEx and its charges. We were in the US in May and left behind a Fitbit activity wristband. The hotel offered to ship it to the UK if we supplied our card details, which we did. But my card bill was for £82 which seemed excessive. Shipping documents said the weight was 1.2kg yet the wristband weighs only 30g.

A few days ago I received a Benjamin Britten 50p coin in my change. My dad told me to keep hold of it as they are rare and fetch quite a bit of money. I searched the coin on eBay and found some examples of the Benjamin Britten coin being listed for thousands of pounds. Have a hit a bit of good fortune, or is it a red herring?

A new meter was fitted and we were billed for the old meter reading. During the years since, despite numerous appeals, we have still not received a gas bill. We are not in a position to pay what I am sure would be a huge amount. However, we would like to clear this up and not leave our family with any financial burden. Can you act on our behalf?

Sky have recently increased its prices meaning our monthly subscription would be £65 per month. We are pensioners and this is the last straw for us - we changing over to Freesat. I wrote to cancel, but Sky insist we speak on the telephone. Why?

Our National Savings and Investments index-linked savings certificates Issue 48 are about to mature. Should we renew them? And if so, should we pick a three or five year term? I am a higher rate tax payer but my wife is a basic rate tax payer. Are there better deals out there for us to reinvest the cash in risk free?

I have been trying to get a tax rebate from HMRC for the past year and feel I am being either fobbed off or totally ignored. I am 68 and receive a state pension of £75.41 a week and a small private pension of £350.72 per annum. On August 24, I received a reply with a cheque for £1 - which I have framed! I wrote again on September 16 but I have heard nothing.

In August last year I received a call from claims firm Falcon & Pointer Limited. It assured me it could get me money back from my bank because my bank had missold Payment Protection Insurance. I was aware of negative publicity about no-win, no-fee offers but foolishly I gave my card details and £238 was taken that day.

In June, my son and I bought a VW Golf for £4,750. I paid £650 of this on my Nationwide credit card after reading in your column that this would give me protection under the Consumer Credit Act. After two weeks, the car gave me trouble and was subsequently found to need nearly £3,000 worth of repairs. I tried to return it to the garage as unfit for purpose, but it refused to take it back.

My brother, who is 84 years old, has just received a letter saying he has won £325k in the People's Postcode Lottery. We are both extremely suspicious, but the letter looks so official that if it is a scam, it might well trick a lot of people.There is a People's Postcode Lottery, warns Tony Hetherington, but this isn't from it.

I need to borrow some money to pay for some home improvements and I'd like to free up some cash to be able to help my kids, but I don't want equity release. What are the other options that I have and can I get a mortgage? Our experts answer a reader's questions.

I'd been charged £632 for the trip I cancelled as well as the £1,363.88 I paid for the second booking.I have been trying to get a refund for months, but Expedia keeps telling me I need to take up my complaint with a firm called Blue Islands, which I've never heard of.

I applied to draw down my annual pension from Scottish Widows. In previous years, this has been taxed at the basic rate, less a little tax-free allowance. I was surprised when all my income was taxed at 40 per cent. Scottish Widows said it had been instructed by Revenue & Customs to apply this to all pension drawdowns. Is this a Revenue ploy to extract money in advance due to the new pension freedoms?

I had a rental property. The tenant left several years ago, after which it stood empty until I sold it last year. British Gas sent me a bill for £3,668. I explained that it was for the tenant to pay and that I had never lived in the property. British Gas said the account would be closed, but now I have been contacted by debt collectors and I fear that bailiffs will arrive over a debt that is not mine.

Thanks to one of the warmest winters for decades, a clothes moth epidemic is predicted in 2016. Traditional natural treatments for moth infestations have involved lavender and cedar. But most households infested with moths find that more sever action is required...

I set up a pet-sitting business and made only £20 in the tax year 2014/15. I called HMRC and was told all I needed to do was write in, setting out details of the cash movements on my business account. In February, I received a £100 late-filing penalty as I'd not completed a tax return. I was told to appeal, but have heard nothing.

Omar Mohammed, of Bespoke Capital Consultants Limited (BCC) and Thames Riverside Investments Limited (TRI), offered a pooled funds investment scheme. My partner and I met him at his Canary Wharf office and invested more than £11,000 for two months.After a long time, he repaid £4,200, but nothing more. We went to TRI's Liverpool Street address in London, where we were told it did not exist, and at Mr Mohammed's Canary Wharf address we were told his company had been kicked out.

Our son is currently renting a flat with his girlfriend. We want to transfer him £15,000 for a house deposit so he is not needlessly paying money to a landlord every month. But how do we protect it from his partner in case they break up in the future?