I spent some time in both Croatia and Montenegro next door this past September.
Croatia is a beautiful place, that is "heaving" in season, when the prices go through the roof. (I'm not sure I would call it a Poor man's Italy at all, as I know plenty of rural, south coast Italian towns I would consider cheaper than the well known towns of Croatia). Croatia is now part of the EU, with the good and bad that that entails.
I loved the southern coast and islands during the summer, but have no knowledge of how much things shut down in winter.
Dubrovnik is an amazing town, and I happily went back a second time after my trip down through Montenegro.
I was lucky enough to find a terrific AirBnB, just a few hundred metres outside the walls of the old city. The owner was amazing, and we became good friends and drinking buddies, of course it helped he was in love with my companion! lol
My trip through Montenegro was about considering it as a place to live.
Residency is easy with the purchase of a home/apartment. Things are cheaper than Croatia, but standards are lower, soviet style. Lots more Russians in Montenegro, but english is spoken in the tourist towns like Budva and Kotor etc. I found more sand beaches in Montenegro than in Croatia. The scenery is amazing, and it's fantastic for sailing and boating in general. Plenty of "super yachts" in residence. Abrovimich's cruise ship was parked offshore, but not sure if he was about or not, as I did not see too many movements from it. The Traffic is horrendous as most roads are single lanes winding around the mountains where it is very difficult to pass safely. One bad accident can shut down all movement for hours, as there are not too many other options.
Lots of Russian girls are on holidays in Montenegro if that floats your boat, Budva especially.
International airport between Budva and Kotor means easy connections to Europe, but obviously there are more options if you drive back to Dubrovnik across the border.
I wish I had pushed on further south and checked out Albania also. I plan to go there next summer