Well whilst you may want opinions to be left out regarding buying one I would still say that if you buy one without a job offer you are taking a MASSIVE risk. But it's your money so why should I care.
I think it's pretty obvious here in the UK, the Airbus 320 or 737NG seems to be the type to go for, you may consider a 757 TR but it's all about your choice, personally I would opt for a 320 TR purely because of the amount of operators in the UK of this type
D.