The price of kenwood ka 6100 in working condition that has not been restored should be around 12k to 16k. Vintage equipment would require some TLC for proper functioning. Also it would be advisable that only go for vintage amps if you have access to a knowledgeable technician or you have a fair idea how to troubleshoot. These things are around 40 years old and even if it is in working condition, sooner or later you would need to restore it. Keep this point in mind before going in that direction.What will be the likely price of Kenwood KA6100 in working condition. Any idea?
My advise would be to read on the vintage amps and finalise a brand and a model you want and wait for it to turn up. Once you lay your hands on it, get it restored and then enjoy it for years to come. Just buying a vintage amp that is available is fraught with problems. You may end up investing some money which may not yield favourable results leading to a bitter experience.