I can give you contacts if you decide for Rijeka region.
Please do!
But what Trofo is saying is pretty much the best advice you can get. All of us here are serious people and not some kids that will fool you around. But if I were you, I would probably hire an agency to help me.
Well, I've worked with 3 real estate agencies last time when I spent 2 weeks searching. They were showing me absolute horrible shit while trying to sell it like castles. There was even once an absolutely ridiculous situation when an owner was batshit crazy and wanted to give us a questionnaire to fill in (it wasn't like "how much do you earn" or something, more like "what's your favorite color"), but this super bulky muscular guy which was our agent stood between us, took the slip of paper from the owner's hand and said "ALL COMMUNICATION GOES THROUGH ME" lmao
In the end we found an apartment on one of the real estate websites and it was the best that we looked at. So yeah I don't trust agencies to do any better than us, all they do is repost the ads with their logo.