Not to put the cat amongst the pigeons.....
All IFAs need to be paid, some by lump sum from the client, and some in form of commission on any purchase (front end load) and commission on how long the client stays in the investment (trailing fees). Different investment houses pay different fees to the IFA so there's not a great deal of incentive in this system (apart from the trailing fees) to find you the best product. Not saying that IFAs are a bad thing (Ruth would cut my balls off for suggesting it!
), just that there's good and bad ones out there, and none are going to give you your money back if the investment hits the wall.
Someone better informed will hopefully come along and give you a better idea which way to jump, but assuming you don't want to risk a loss (not maybe the best idea if it's going to fund yer mum's future life) I'd be pretty bloody conservative.
If it were my cash (with the same objective) I'd diversify to reduce the risk and go for a mix of premium bonds, the highest interest bank account available, a couple of tracker funds, and a small slice of reputable but volatile funds. Try to keep those likely to earn you the most interest in tax free accounts (ISAs) so you don't pay tax on the interest. If your mum trusted you and Dan enough to open an ISA each using the money then you'd get three times the tax allowance meaning £21k could be invested tax free. (I think, may well be some issues with doing this that I don't know about).
Cheers,
Ali