When someone balances your rotatingassembly, do they need the balancer and flexplate as well? Would it affect the balance if I bought an aftermarket balancer later in the future?

The reason I'm asking is because I'm on a budget and am trying to differentiate what I can buy now and what I can buy later. I was thinking of balancing my new parts with my stock balancer and flexplate, and then buying an aftermarket balancer later since the ones I've seen run a couple hundred.

Thanks!

gaz, (Name ??)
First of all, before everyone "nit picks" me on this answer, it is kind of simplified. There are many things that go into a balance job, but I dont think you want all the technical details.
So ...

It really depends on the engine. If it is "externally" balanced like the 454's and 400 Small Blocks, then you must have the damper and flywheel. On most other Chevy engines, you dont really need the damper and flywheel as they are balanced seperately and are really pretty well balanced from the factory. In either case, you should be able to relpace the damper and flywheel in the future IF the balance shop does the job correctly, which means not drilling on the damper and flywheel.
By the way, I would think that whichever shop will do the balancing for you would be glad to show you haw a crankshaft is balanced. Its a lot easier to explain with the setup in front of you to see.
Hope this helps,

I am running a 400 small block, I should've specified that earlier.

At what ET are SFI balancers and flexplates needed? 11.99 and faster?

10.99 NHRA, IHRA ????