Investing in a Central European city without sufficient research is probably the worse mistake that smaller overseas property investors have made over the past few years. Many people believe that if they invest in any sort of property in a city, where prices are increasing, that they have made a good investment. However, it's much more difficult than that and finding a quality apartment, which will give good returns is not easy to find in any developing property market. The truth is that the vast majority of apartments in almost all CEE cities are not good investments.
From my own direct experience in the Budapest market and of research I've carried out in Prague, Bratislava, Krakow and Warsaw, I've seen investors rush towards the latest popular spot, purchase one of the first flats they come across (usually off-plan and out of the grasp of locals) and then two years later, wonder why their property hasn't increased in value.
Most cities in CEE have good economic potential for the future, but choosing the right property is paramount. Don't feel forced into it and take your time until you know you've found an investment, which suits you.
Budapest and Warsaw are generally predicted to be those with the most potential, with low debt levels, low unemployment and the highest FDI in the CEE region. Bp has better rental returns and higher spending power (you wouldn't think it at the minute due to the austerity programme!) but the Warsaw market is currently appreciating at a higher rate.