The flooring installer should have undercut the bump out and slid the flooring under it. That would cut down on a lot of trim work. A simple quarter round or shoe base would cover up the gaps.

I would agree with your husband here. Build out the base of the closet built-in and install a continuous baseboard. It keeps it, clean and simple. Otherwise, trim guy has a lot of mitering to do.

I agree .

I agree. You cannot go 'tighter' with cuts. The expansion gap is there for a reason = to allow the floor to move without bumping into anything...like the shelving bump outs.

Remember: the expansion gap = SAME AMOUNT as the floor-thickness. If your floor is 8mm thick then everything must have 8mm expansion gap. If not you will run into trouble in the future.

Go ahead and start measuring the expansion gaps around the house. If they are 'too tight' you will have issues in the summer when everything expands. Winter is the 'shrinkage' time because the heat is on = dry indoor air.

That’s for this information! Super helpful! I will check for expansion gaps and use the baseboard for trim around the closets.