Make sure you check out a Honda (or kymco) NSR before you commit. They are two-strokes and therefore very cheap to throw a new piston in if you wanna rebuild your engine (plus they are twice as fast as the Yamahas).
I’m not sure. It depends a lot on the condition of the bike. If it’s from a shop then I’d say you don’t really want to be paying less than 20,000 or more than 30,000. You should get something decent within that price range but do be prepared to a) get any obvious problems fixed up before you buy it and b) spend a bit more money later on other small problems that may crop up and on getting it running really nicely.
Actually there is a really good mechanic friend guy trying to start up a shop near my place so I should be able to get the bike taken care of really well.
So if anybody sees a Yamaha SR 150 not too old for sale please post on here.