I have a friend that has a 78 CB750K That he quit riding and parked in his garage 20 to 25 years ago. Has rust on it. Don't know about the gas tank. Chrome wheels are pretty rusty. Has 14,000 miles and original tires. After market 4 into 1 exhaust. Engine is not froze. He said to make him an offer. What would be a fair price. I would want to put it back on the road to ride not show quality. Would like to find a decent factory exhaust 4 into 4. I know that is a long shot. Could it be bought and road worthy with no more than $ 1,500.00
$1500 is hard to tell. It will need a battery, oil change, maby tank De rusted, tires ETC.
without a pic it is hard to tell... but between 500-1000 is a start for an offer for it.
We can help with the problems involved in getting it road ready.
Not the same pipes...your 78's will cost more. If you have a tight budget, just clean up the 401 and keep your eye's peeled for a deal on a better one or affordable stockers. You will see them sell cheap at times, but if someone with $ doing a resto comes across them forget it.