Well, there's still plenty of them out there, many complete abominations, but they're out there. I've owned many bikes (British, Italian, American) including several 400f's over the last 45 yrs, in various incarnations, and most recently a '76 550f and between the 400's and the 500/550's these are by far the easiest bikes to repair/restore and modify and resell. Do the maintenance, change the oil and you can ride 'em day in and day out with nary a problem. These bikes are still plentiful, there's still a great aftermarket and for the most part it's still an affordable aftermarket. That BaT sale is an aberration, buy one, bring it back to life, ride for a year or more and then sell it. It'll return its investment and maybe a smidge less, maybe a skoch more what else could one ask for.
I put up an ad for a bike last fall and it had the 400f in the background, got more inquiries on the 400f. Everyone wanted to know what I'd take for it, I told 'em, "$5500", complete silence. So yeah, an aberration.
