The only thing I'd let near my cabinets would be a brush.

But it depends on why you're having them painted on site, and what you're after.

If you're looking for an as-close-to-impermeable-factory-gloss-finish-as-possible, then a paint spray with a lacquer topcoat may give you that look.

Is that the case? What is the thing you're most concerned about? Color? Durability? Smoothness of finish? Mess?

If your painter sprays a finish, it should be in a shop with a clean room. Otherwise, dust and flotsam make it into the finish. I would NEVER have a paint finish site sprayed. NEVER. The biggest bonus to shop finishing is having a clean room to do it it, and (if they have the technology) the conversion varnish topcoat. That adds a layer of durability that you just can't get with a standard brush applied finish. But, some people prefer the brushmarks of a "oldfashioned" brushed on painted finish. If you are one of those people, then site applied will be fine, as you're into the imperfections that lend it character and charm and traditionality.

Alder is a beautiful (but soft) wood, and I would have thought that most cabinet makers wouldn't waste the upcharge to that from paint grade maple. It's generally stained as it has a beautiful grain pattern. Painting alder would give a woodophile the equivalent heebie jeebies to fingernails on a blackboard!

THank you so much for your responses. I will clarify. The painters we have talked to will take all doors and drawers offsite, but will paint the boxes here. I wanted to purchase cabinets from a cabinet shop that also painted, but it was much more costly compared to the price I received from this cabinet maker who has worked with many of my friends. I'm looking for a finish that is smooth and durable. I would have also preferred to buy cabinets with a baked on finish for durability, but again, cost won out. I'm still considering a stain on the island, because I too like the grain in the alder.