Last time in Prague I went for sushi and a couple of Sapporo beers in one of the few good jap restaurants in town, some of you may argue that sushi is a western luxury but still i feel the need of telling you that i paid exactly as if i had been in Berlin or Paris.
Of course one can feed himself with potatoes and pork and save a little bit but we were talking about lifestyle here.
As far as rents are concerned it will not help you much if you speak czech or not, they are in the range of 500euros/month anyways (I'm talking about a decent flat in town).
Leaving your car at Dejvicka is not a desirable practice since car theft is one of the main recreational activities of the czech rep.
My suggestion would be Net Jets: good company, good T&C and the possibility to be based in Prague.