Mics on each drum can be convenient in mixdown, but it's not necessarily the be-all end-all to getting a good drum sound.

You can get a decent, hell even better than decent recording with just a few mics. It's all about tuning, mic placement, and the room.

A box with 8 inputs is plenty for someone just getting into multitracking, in my opinion. The less mics you have to deal with the better. The overheads are very important, start with just a pair of mics above the kit. If you want to control the kick better, throw a third mic into the mix.

Experimentation is key.

Ringo's drums sound pretty good, don't they? OK, dated perhaps, but still good...

I like to brag about being the laziest engineer I know. In that respect, I'm really into LESS IS MORE, KEEP IT SIMPLE STUPID. So perhaps like Rudy Van Gelder, Philip Glass, I like to see how few microphones I can get away with on a drum kit and still love what I'm listening to. Usually it's 4 but sometimes 3. Of course just to make things look good, because, hopefully, you are being paid, you might want to put microphones on all of the drums and then some. You can never have too many microphones on the drums because you're only going to use 3 or 4. The same is true for orchestral recordings. You hang 8 microphones and put out 8 highlight microphones onstage. You end up using the front 2 or 3. But you'll be ready when something doesn't go right. That's called redundancy. Redundancy is just a fancy word for smart. But it's so much easier to spell smart accurately than redundancy and I find the term lazy is even easier to smell than fart.

Joking back the the tears
Ms. Remy Ann David

Oh my... one of my favorite subjects.... NOT!

It depends...

As Remy said... less is usually more... but it depends.

If you have a crappy room, more mic's to do close micing is sometimes the thing to do. How many more??

Kik in
Kik out
Sn Top
Sn Bottom
Hat
R1 Top
R1 Bottom
R2 Top
R2 Bottom
R3 Top
R3 Bottom
R4 Top
R4 Bottom
FL1 Top
FL1 Bottom
FL2 Top
FL2 Bottom
etc... ad nausem
OH L
OH R
Mono Room (Stereo Rm L)
(Stereo Rm R)

And sometimes it STILL ain't enough.

But most of the time I get by with Kik, Sn and a pair of OH's.

With a good room, and investment in a good pair of mic's a pre's... a LOT of great music has been made with just two mics... and even one mic.

It all depends...

(Is the can of worms officially open now?)

Since you are just getting started with this, any more than eight tracks will tax your ability to mix a good drum sound even if you had the ability to record it. In other words, if Max sent you his hypothetical 24 drum tracks perfectly recorded you'd just make a mess of the mix unless you turned almost all of them off. As everyone else has suggested, start out with three or four mics (kick, snare, one or two overheads). Work with that for several months. If you can't get a good sound with that, you'll never get a great sound with any combination. The key to getting a good sound with three mics is the drummer, the drums, and the room (in about that order). If you don't get those right, 24 mics won't help. Eight tracks will give you room to experiment a bit, but will keep you from going too crazy. It will probably be years before you would really benefit from a much bigger interface.

If you decide to go with a 8 channel interface and you are worried that you might need more later buy one that has expansion capabilities. The FP 10 can be daisy chained giving you the option of up to 24 channels. Other interfaces may be capable of this as well. The 4 mic set up for a beginner, hell even an experienced engineer is sage advice. Mic placement is critical and tiny adjustments can yield whopping results in tonality. Besides if you are just starting out 7 mics times a modest $200.00 = $1400.00 in mics alone. It would be difficult to make good decisions on exactly which mics you would be best with. If you start off with 4 you can at least get an idea of what these are doing for you and add more as your ability to hear results improves.
Did you listen to the sticky in pro recordings re: drum and snare mic samples?

So the synopsis of my fellow recording heads has given you much to chew on.

Drums are the make and break glue for getting pro sounds on a recording. Small, poorly recorded drums will reflect throught the entire recording.

And then theres the Mixing! A large number of poorly recorded drum tracks does not translate into an easy time mixing. Lots of anomolies occur when you record drums. So Keep It Simple Stupid is a very good point of reference for a beginning student of the recording arts.

If your room is not treated or isnt a decent size to record a live kit in, then perhaps an investment in a quality drum program is the ticket. Good pads and an easily adjustable program can still give you the 'live' feel, just not the live headache and struggle you will undoubtedly encounter on your quest.

Recording drums isnt all about simply sticking a mic up an VOILA! instant Chad Wackerman! The room, the kit, and the player all have an equal partnership in attaining a good drum recording.

And then theres MIC PLACEMENT.....Ha! Thought you were ready huh....