Have you heard of a national or local government organisation called BTI
My girlfriend is having problems, she says, with selling her apartment. When a buyer came along the property was inspected and was said to have been altered and was dangerous. Further the BTI got involved and said that the apartment had to be returned to original spec before sale and a fine would have to be paid if this was not done in a timely manner.
I Googled "bti housing ukraine" (you didn't specify Ukraine or Russia) and see references to a "Bureau of Technical Inventory" involved with housing and real estate. Click the link to see results.
But I'm sure five seconds on Google would have told you the same thing, so I assume you really meant to ask if her story is suspicious.
To THAT question I probably have a more helpful answer: As soon as I hear that a Russian/Ukrainian girl is having some kind of high-cost/high-drama/high-urgency situation my red lights start flashing.
If this "girlfriend" isn't someone you've at least met in person and with whom you've spent some significant in-person time with absolutely no cause for concern, then all my chips are on this being a scam.