Hello!
There is the very popular site http:// olx.ua/ where you can find any variants. But it has no English version. You should to ask some Russian/Ukrainian speaking friend to help you. Or find an agency via Internet.
If you need rooms by the day, call my friend Andrew, he has a business in Kiev, leasing appartments. Prices: from 400hrn ($30) per day for double room in the center of Kiev.
Andrew: +38 099 3798888, +38 063 9538888
Good luck!
Leonid
