First off, you'll find a nice cache of 21 pounds (Scotland uses pounds, not euros) in the nightstand in Nancy's room. That's a good start.
You can get more (and you'll need a lot more than 21 pounds to finish the game) by making cookies at the deli outside the hotel.
How do I make cookies?
Finally, if you click on the little glints you see around the game, they'll yield up caches of money to add to your collection, between 1 and 10 pounds each time. Neat!