We are building a new house. We had the unfinished hardwoods installed before the cabinets and trim. The hardwood company said they always sand, stain and poly with two coats upon installation then after everything else is complete they come back and do the third coat.
Is this a normal sequence? Our trim guy says he's never seen it done this way. That they should have installed them but not done any finishing until the end. I'm wondering if the hardwood company pulled a fast on with me.
Thanks!

I usually do it that way also. that way there is no chance of damaging the new cabinets or trim work. Most of the contractors I work with also prefer it that way. It sounds to me like your trim guy doesn't want to be careful.

Sometimes we install sand and coat twice before cabinets and trim and other times after cabinets and trim. it doesn't really matter. We do however always final coat after everything else is finished including the base shoe. It sounds like you'll be in good shape doing things as you describe.

Common in my area to install sand and two coats before trim then come back when everyone is done working on the floor to do the final.

One possible exception...
We have become extremely proficient with European hard wax oil (Rubio) and it is done in one coat... So if you're thinking of selecting this type of finish, you might need to sand and finish after a large part of the rest of the work is done.
And yes it's risky for wood floor guys around finished cabinets etc.... But tell me... Don't we refinish homes with all that stuff in there already? Just sayin...