Yep..I wouldn't sell mine for a dime less than 5k.
eBay is one thing, but on a recent trip when I was pulled over to refuel, some guy came by and offered me his Jeep and a trailer for it. The demand is very high for any SOHC CB750 in unmolested condition. I totally agree that these will continue to get more and more dollars.
$3000 is quick spent when restoring a CB750.
+1. $3,000 won't be enough for a full 10-point restoration, either. I have at least 3k into mine, and it ain't no 10-pointer, but it turns heads and I always get (bothered) praise. It's nice enough to win 2nd place for "Best in Show" out of 35 bikes at the local VJMC event. One guy approached me at a classic salvage yard and said he's never seen a 78 look as good as what I did to it and that it was "far cry better than stock." He gave me his card and told me to contact him before I put it for sale in the future...it does have a tendency to fool people.
Plus, they are awesome bikes. I would love to get a chance to ride on an older SOHC, but I must say, these models are bullet proof, smooth, perfectly balanced, and powerful. They're fantastic bikes. Even with the "cheaper looking" pipes, I think they sound the best too from the earlier SOHCs that I've listened too (was not impressed).