The best I can come up with involves more money.
You could do as I did and train for a Heavy Goods Licence. A licence allowing you to drive a rigid lorry (i.e not an artic) will cost about £800 and take a week to train for. I went on to do an artic licence which costs a lot more (£2k) and requires more training but there is no need if you only need money short term, although there is better money on artics.
There is stacks of work with lots of driving agencies. Most will allow you to work on any day you like. You can earn between £400-£600 a week and you will not have to dodge the Inland Revenue.
Not a very good suggestion as I know you have no money (sorry!)
Bill