I'm getting ready to start the CCNP, and I'd like to build a lab environment to work in. Cost is a significant concern, but so, too, is the ability to get real hands-on practice on my schedule (hence, I'm not too excited about rack rentals). Below is what I think will be a good balance between cost and functionality. I'm looking for some critiquing of the lab. Perhaps something along the lines of 'you can do the same for less if you look at model xyz router', etc.
Equipment I already own (from the CCNA lab I built): 3 2501 routers, 1 2650 router (not XM, 1 BRI, 1 FE, 1 Serial), 2 Catalyst 1900s.
Additions for CCNP:
3 3640 routers, 128D/32F, IOS 12.4
1 3550 switch
1 2950 switch
1 2924 switch