You might also want to price out what it would cost to do it yourself, but instead of using spray foam using rigid foam and then great stuff to seal the panels to each other and the framing.
Not trying to be a smart ass, but...............have you ever tried to use Great Stuff, overhead, like you are suggesting the OP does, under his floors? The reason I ask, is that I have, and it is an epic cluster-F. I did a volunteer job, repairing the underside of a motorhome floor, after some handicap retrofits to the vehicle. The manufacturer sprayed the entire underfloor with closed cell foam, and there were several chunks removed so we could bolt a new wheelchair lift in place. Repairing these overhead spots, with canned foam, left me looking like a monkey trying to screw a football. The only way I succeeded was to bridge the missing areas with duct tape, slit an opening in the tape and spray the "pouch" full. I literally wasted 5X as much as I successfully applied.
I have used great stuff overhead on gaps around HVAC ducts, bath tub drain cutouts, and holes for electrical wiring and I have used great stuff to seal between panels of rigid foam and to seal rigid foam to the framing; granted I have not used great stuff to work on rigid foam overhead so maybe there is a magic situation that makes it worse.
If you are careful in your cutting then the gaps between foam boards or from foam to framing should be minimal (think friction fit to quarter inch). It sounds like the holes you were trying to patch were a bit more sizable and perhaps you needed to use the gaps and cracks formula.
I agree the seemingly single-use cans are a royal pain to use overhead, I switched to using the pro-gun and with the narrow tips added it is much easier to control and add only a small amount.
Great Stuff can be great, for filling voids, or other applications where it doesn't need to defy gravity until it cures. If you get the urge to use it overhead, stop. Put a few globs in your hair, let some dribble on the floor, and toss the can in the garbage. You are getting the same result as applying overhead, and not wasting as much time.
I was providing an option other than a DIY spray foam for the underside of the floor . . . if you think that great stuff gets in your hair and on the floor, I am willing to bet that a DIY spray foam kit will make a bigger mess of the floor and your hair.
I will not deny that great stuff will make a mess, ooze out of the tip, drip on the floor occasionally, and get on your hands. But all of that can be dealt with with proper setup, equipment, and clean up (think gloves, a plastic cover on the floor, and acetone for timely clean up). But, to be honest, from your description, it sounds like you either exceeded the purpose of the formula you were using (trying to fill a larger/deeper hole in one pass), were in too tight a quarters, or need a little more experience using great stuff.