if u don't have 1st hand knowledge of the market place (be it Bulgaria, Hungary, romania or any other far flung overseas place - especially eastern europe) u d'ont stand even a remote chance of making a good investment. D'ont ever, ever, think that a bargain or solid investment will be presented to u - especially so if your dealing with an agent. Agents are commission driven, they could'nt give a monkey's about u - no matter how much they might appear to.
If u are still feeling brave - I would consider Germany to be the best bet in Europe at this mo in time. However, unless u have the assistance of a truly independent person with good knowledge of german property u are extremely likely to buy poorly than not.