The trihulls are goldmines. 
No one wants them - b/c they're ugly. 
Floors and transoms are usually built like crap (rotting out).
Lots of them have well cared for Freshwater Volvo parts.
Yolo county landfill only charges $60 - 100 bucks to drop them off. 
I don't know the differences b/w the Volvo 200c and your motor, but you'll get an extra 280 drive and get a chance to test it out. 
I've been selling off some extra volvo parts on ebay and there's a pretty good market for the parts. Especially the upper drive units, props, and the trim systems. 
That boat has a dual axle trailer (which you can unload for $500 - $800). I'll bet you'd make money on the deal if you talk him down to $1200 - $1400. Sell the trailer, electronics, outdrive, Teak swim platform, etc. It takes time, but if you're look at a few years w/o a boat . . . this might be a lost cost option. 
  
