SK Grimes just posted a CLA'd Toyo View 45D with a bag bellows & lens boards in the APUG classifieds for $300. Add a decent wide-ish lens and the bits, and you've got a super good set up for architecture, and you're also still going to be well within your budget.
It's not a pack camera, much more suited to architecture, working out of the car, etc.
Consider a start with this type of set up, build up a lens selection/collection, and then add a field camera for hiking, etc. Since you've gone against all good advice from "sane" persons, and fallen into the abyss, it's unlikely that this will be the only LF camera you will buy, but rather just the first.