Address card (for the purpose of mobile phone contract)

Hello!
I'd like to buy a mobile phone with a contract in Budapest. I am a non EU national, have no residence permit in Hungary. I do own an apartment here and live here from time to time on my tourist visa.
The mobile phone provider requests an "address card". They were not really able to explain me what it is... just kinda proof that i own a property here and don't intend to sell it (that's what i understood).
Any ideas where to get it, and whether it's at all possible to get without a residence permit?
Thanks

If you own the apartment, you should have a "tulajdoni lap", the provider should accept that. They must have been referring to "lakcimkartya", but you won't get one without residence permit.