I'm not talking 'loaded'; just base machines here. Even a 'loaded' A500 is laughable next to a base A3000. A well-equipped A1200 (other than AGA) just starts to approach it.
The base A3000 is so much more bang for buck it's not even close really. I forgot to mention the built-in scsi dma controller and up to 16MB of fastram on the m/b (though these are rare zipp chips); fast slot compatibility with A4000-style accelerators for expansion; built-in RTC and battery. If you can find a 25MHz A3000 with 8MB of zipp memory, w/ keyboard/mouse for <$150.00 you really won't be sorry. Some A3000s even had high density floppy drives built in (Chinon FZ357A). It was simply the best machine C= ever made, imho.
A 'loaded' 32-bit Amiga w/ 68060, 3D graphics card, 128+MB ram, ethernet card, fast scsi controller, etc. is going to run you probably another $500+, regardless if it's an A3000, A4000 or A1200. The point is when you're ready to invest such money, you'll be much happier putting it into an A3000.