How much it cost to rent flat in Crimea?
I think your question is too general, because you can rent 1 room for 1 day or three-storey house for 1 year... 
Perhaps someone living there can advice me 
Ask this guys, https://bitcointalk.org/index.php?action=profile;u=65011
https://bitcointalk.org/index.php?action=profile;u=133293
This season girls and houses will be cheaper than usual 
It's unlikely because every second girl in Moscow is from Ukraine already.