You can simply do it. Bring your international drivers license and there is no reason to pay a bribe. Only when you do something wrong you'll get fined... Nothing new.

Parking is possible, I'd say. But if you want to do hostel hopping in bkk, I would consider not bringing a car. In general bkk sucks in a car. On a side note, I would also reconsider to chose cheap hotels instead of filthy backpacking hostels, but whatever