Bob
Here is a sure fire way to make yourself a few million pounds.
Borrow a lot of money on any interest rates you can get.
Use this money to design and build a time machine. Not the TARDIS style, the box is hard to find and you don't really need the spatial ( relative dimension ) aspects.
Forget repayments. devout all your time and effort to get it to work while you are still able ( good eye, sight nimble fingers etc ).
Once you get it working if the bank notes are still the same style as they were when you took the loans out then go forward in time and get the next weeks lottery numbers. Come back and use them on a ticket.
Now you have a large stache of cash. Go back right back to the day after you took out all the loans and pay them off. If the time taken to build it is too long and currency has changed then you have to win the lottery the week after you took out the loans. Make sure you keep enough cash of the time to buy a ticket.
Then you can whizz around time, meet Billy Piper and set the world to rights before it goes wrong. Nip forward, find where and when that asteriod arrives and deal with it.