BTW, those cabinets will easily last 100 years. And will only get better looking with age and use. If some future owner were to ever replace them, it'd be a damn shame. I'd take them with me if you ever move!
Consider yourself employed for several years if I ever win the lottery!
The prices on Baltic Birch plywood are very regional. I was paying $50 a sheet in Alaska in the mid 90's. It's still going for around $20 a sheet in South Texas. Here in the bay area it ranges from around $60 - $90.