I have a Kowa outfit, 4 lens set, bought mine used over 30 years aso. Do not have the teleconverter or extension tubes. There are a couple of folks who repair Kowa's but parts are hard to find. Lens are fair to good, but not on the par of Ziess or a modern Japaness lens, I can get a quite good 16X20. The only issue that has come about which I have not found a reason for is that HP5 will not cock the mirror return as the film is advanced and the mirror locks, has not happened with any other film type such as Delta 400 or Tir X. Are the lens the chrome or black versons? A 66 rather than a Super 66 I guess older chrome. I would pay $450 to $500 for a clean set up, but consider finding a Super 66 with mirror lock up and interchangable backs, last model made as your primary body and use the 66 for a backup. I think a super 66with a 80 2.8 and 250 black lens sold for $495 at a local shop a couple of months ago.