1)In a country like Moldova I refuse to pay more than 10 EUR per night for a place to sleep - I assume that is not enough for a hotel?
Oh yep! 100%. If hotels are too expensive, try this http://www.makler.md/ .It is a Russian site,but hope you'll find something interesting for you.
2)If your Russian is intermediate, i suggest you to buy a road book and a pocket dictionary German-Russian-German.
3)Here we have buses, cabs, and maxi-taxis. Maxi taxis are minibuses that are used in public transport.
4)by the way: concerning train schedules :http://www.railway.md/ro/
If you want to acquaint yourself with Moldavian culture and traditions,..... visit http://www.thehandicrafts.net/
Good luck and welcome to Moldova!