I did a couple of classes last year, but stopped during to busy schedule. Depending on the school, some offers one to one or group classes. I think Yamaha offers group class, while the other small music school do one-to-one. Personally, I prefer one-to-one (though I never tried the group session) because drums are ALOT more complicated than it looks! You need to move both hands, and legs simultaneously, but all at different beats/speed. If you are in a big class, I feel its really difficult to focus. You need ALOT of concentration to really do it, at least till you become fantastically good.
I cant remember how much I paid previously, but I think its less than $100/month for a one-to-one session, once a week. You need to get a textbook (less than $30, which is recommended by your drum teacher) and a pair of drum sticks (not the chicken drumsticks

). As a beginner, the basic drum sticks are good enough, and that should cost less than $20. There are alot of fancy onces, but in reality, they are just for looks. The initial investment is quite cheap, until you decides to buy your own drum set.
I understand that the smaller music school have studios for rent, so you can pay about $7-10/hour (thats the rate for my previous school), and practice your skills. This is a good alternative till you decide if you are good enough or ready to get your own drum set.
Hope these info are useful!