Well, there's a sticky post in this forum which has a lot of FAQs which cover b16 swaps, ZC swaps, etc. which will detail everything you need. Also, if you're considering a ZC swap, definately check this out:

http://thenew.gamesbbs.com/~dmoore/z...d%20It%20Cost?

this page is totally comprehensive and I've found it to be correct insofar as I've tested it.

good luck