Just to point out as noted, those (50) runs are 300' runs. You're talking about around (12) 1/4 mile passes on this engine. There's not a lot of time on this thing.
I've been surprised too. I know it seems like a lot of money, but as some people definitely know, it's going to cost a ton more to build it from scratch. I've only had one offer so far, and that was for $8,000. Not gonna go that low.