I'm in the same spot as you, installations are hindering me considerably.
When I was doing that, among other things,(and before I went into cabinets fabrications) most of the time rates here in Florida were $20, $25 or max $30 per cabinet, as for 8' stick of molding too, $1.50 per hardware hole. That was what cabinet companies or contractors were willing to pay. A somewhat higher quality cabinets and direct contact with the customer (so no middle man) could get you $45 per cabinet.
That was 2-3 years ago. Supposedly (according to a friend of mine who was in cabinet installation before me), few years before that $45 per cabinet was a 'standard', i.e. even with contractors and lower end merchandise, but not so much these days...
This is all for 'regular' kitchens in rental and residential homes, i.e. up to $10K kitchen value or not much more.
I have no direct experience with high end kitchens in high end homes.
In my work, more than 50% of time (possibly even more) is "lost" on low-skilled or no-skilled work like loadaing/unloading materials and cabinets, demolishing, cleaning installation place or my shop, packing/unpacking tools, handling extension cords, buying this and that, scraping loose paint or old caulking, taking trash to the garbage container and so on.
So, my next step is just a simple helper, to relieve me from such things, and if I can train him do do something more, I will, and than I'll just get another helper.
Well, at least that's the plan.
Also, buy yourself the "E-Myth Revisited" book.