Unfortunately I'm not selling (because I like mine), but in that price range you'll be pretty much going for a Pentacon Six, Kiev 60, or Kiev 88 (in its many variants), so I can offer a bit of advice about them.
I've got all 3 (my 88 is an 88CM), and they've all got their strengths and weaknesses.
I prefer stop-down metering, on the P6 I've moved the aperture pin in the body out of the way (easy and reversible). On the K60 there's a stop-down lever I can move with my right middle finger. On the K88CM there's nothing (so it only works in stop-down with my Zeiss 120/180/300 lenses).
P6 has a self-timer instead of the K60's stop-down lever, the other two don't.
Maybe it's just the copies I've got, but my K60 seems a lot better built than the P6, more like a german-precision machine than the german machine. My P6 may have just had a hard life. The 88CMs have an apparent bad reputation for build-quality, I got mine from fleabay with a 'recent CLA' tag, I've never had a problem.
I've never used the P6 meter, i've got an adapter to put the K60 meter on my P6. On the K88CM i've got the centre-spot 45-degree meter. I've put a brightscreen with centre-split-prism in the P6 (the other two came with one already). Calibrating is easy (I match it to what the metering says on my EOS3 and/or 7D with the same lens on adapter).
Don't get the K88 unless it's a steal, go K88CM for P6 lens-mount, you can then still put native K88 screw lenses on it via a $20 adapter.
Lenses for anything in P6 mount are good (the Ukranian versions are good designs, just iffy QC). Same as buying any other lens 50 years old, how it's been treated makes more difference than how it left the factory. Exakta66 lenses are the best and newest, but expect to pay $500+ each. Soviet lenses go sub-$100 (mostly sub $50), Zeisses are $50-200 depending on condition.
Other than those 3, I don't think you'll get a 6x6 for under $200 (at least, not including lens). The cheapest Hassies I've seen are still above that body-only, same with SL66. Of course they're better, but you pay for it. Not much experience with Bronicas, but from what I've seen you'll also be lucky to get something under $200 (that works).