Can't speak for anyone else, but I will not purchase a bike I can't hear run, or ride.
Can't say I wouldn't bring the old compression tester and run down the street with it... no battery needed. A lift of the seat to see if the harness was smoked. A chopstick down the spark plug hole, and with a certain crank position, a push on the piston to feel for a bad crank/bad small end. A better/cheaper bore scope than I have. A plug check. Get it running and ask your price. Not running, yeah, whatever you say [seller] it's worth this much.
Prototype, schmototype, seller, it's a fucking part bike. All I see are bike parts out of a catalog, you wanna sit on it and wait for eggs to hatch or take $4k and run with the money, guy! Comp and a stick calls the ball for me. Oh, it's been dropped> 3K or I walk.
Then it's 12 bucks for a large can of NAPA carb dip and 20 minutes of wow look at that once you wash it off with water. Injected? A can of gunk and a shot glass, where's the injector to go skinny dipping?
Comp: Has to be well above 170psi or better.
Spark: An old HD ignition off an evo engine family, or aftermarket. Wire the bike with minimum head/tail/brake.
Fuel: NAPA to the rescue.
New frame and front end... your call on it crashed or dropped. Does not look dropped, but neither is this post specific to this bike, but any bike buy.