Baachitraka,
Since you state you have no desire to set-up a studio, that means you want a camera that is easier to hand hold and carry around.
With that said, I would advise against a RB/RZ; they're too heavy. Also, to keep costs under control, I would not recommend any cameras that are extremely old, like many folders with bellows and range finders that can become un-coupled and mis-adjusted, or cameras that had limited or short production runs like some of the offerings from Koni-Omega.
Stay with something more main stream, or produced in such large numbers, that initial cost of the camera is low, and parts, (even through cannibalization) are more readily available.
For you, I would highly recommend a TLR. Yashica and Mamiya are probably your best value, long term. Mamiya TLR's are plentiful and so are the variety of interchangeable lenses that go with them. The Yashica TLR's don't have interchangeable lenses, but are much lighter to carry around. Nice operable, "user" Rolliecord's, (poor mans Rollie), and Rollieflex's, (rich mans Rollie) are often priced outside the range of what would be considered cheap or economy.
With patience, a Yashica D, LM, 12, or 124 model can be purchased in user condition for no more then $75.00 USD. You don't need to buy into the inflated hype of the 124G. Whichever model you find, try to find one with the matching case.
Good user versions of Mamiya C series TLR's can be found, (complete with view finder attached and one lens set) for about $100.00 USD.
Don't worry so much about a matching case for the Mamiya TLR's. They're over priced and a genuine PITA to use.
The Mamiya TLR's have bellows, but unlike folders, there are actually three (3) bellows. The outer bellows can be seen, but underneath, there are two more independent bellows, one each for the viewing lens, and one for the taking lens. A little bit of crinkle or crumple on the outer bellows is not necessarily a deal breaker.
There are seven different lens focal lengths available for the Mamiya TLR's. ranging from the two wides, 55mm and 65mm, the standard 80mm, the short telephoto or long standard 105mm, and then the three long telephotos, the 135mm, 180mm, and 250mm.
I love my RZ, but my TLR's are much easier to carry around, the results are impressive, and I never have trouble finding parts or service for TLR's, even in my little Podunk town.