Any information based on personal experience of this would be useful.
Standard of finish.Firstly there are different
standards of finish in all ex-communist countries.
So depending on what you buy and how good the person looking after the property is and the people who fit it out are, is beyond your control.
Like everywhere, you can get cowboys in to do the works and it all blow up in your face.
Then you will have to get someone to furnish it.
All these are extra costs ontop of the price of the apartment (this is changing).
Connecting to utilities.You will have to sign up with the dreadful electrical company Enion, that means you have to go to their office with every single paper and go through "the process", you can't just give them money, oh no!
Same with the water and gas companies.
P.O.A.I am guessing you are leaving the apartment to someone you know and trust to look after.
If so you should go to a Notary here in Poland and give them power of attorney to preform utility functions. I recommend you do NOT go to a lawyer, lawyers here are very different to those in the U.K. and the Notary might not accept a lawyer's "interpretation" of what a POA is. Plus Notaries are cheaper and even if you do go to a lawyer, he will just write a letter and send you off to the Notary.
The almighty stamp.Keep all your paper work. Just put it in a folder and keep it somewhere safe. I know it sounds easy but the amount of people who are not used to paperwork and then waste time getting original copies, is silly.
I like the wording "original copies".
Internet banking.It is crucial you get a bank account here in Poland, make sure that their internet banking is in English, unless you prefer to leave that end of things to your other half.
Terms and conditions.I don't know you, so I will talk as if you know nothing, the contract for your purchase is very important,
terms and conditions, penalty fees for being late, a list of what finish the investors will provide, payment schedule etc...
Tenants.Tenants will hardly ever look after your property very well, so use durable materials.
I would avoid first or second year students (partying hard) and women with childeren can register in your apartment and you could have to buy them out (but in fairness I have never actually come across this).
I also recommend you visit about once a year to keep tabs.