a book i found for electrical labor units is a couple years old but its mainly commercial equipment. I dont see 1 gang or 2 gang nail in boxes or 4'' round boxes.
im not asking for any ones personal labor units but If you have NECA i would appreciate it on these items. Im not an estimator ( not yet ) Im just a novice. i know i have a long way to go.
1 gang non metallic nail on box
2 gang ''
3 gang ''
4 gang ''
AND
6'' recessed cans IC
I don't do residential, but I am an estimator. I hope this isn't considered off topic by the new guidelines. I don't think the NECA manual has NM boxes, and NECA labor rates are generally too high for competitive bidding. also, estimating is not a one size fits all perfection or it would be called exactimating. All that said:
For a blunt don't care to learn answer
1 gang .15
2 gang .15
3 gang .17
4 gang .17
6" can .4 must add additional labor, .15 for 8 foot ceiling, .2 or so for higher ceiling, also more for slope adapters, or wall washer adjustment if you want to be closer to actual. Or you can just use .25 for all standard, and use .35 for wall washers since you will be going back and aiming after they are energized.
For a more in depth answer.
You need to extrapolate from what you have available. Really a 1 gang and a 2 gang should be virtually the same time, and a 3 or 4 should be slightly more because you can transport less of them. So, for example, I show a 4 square bracket box at .2 competitive and .3 NECA. A plastic boxes should take a little less, but not a lot because much of the time is in layout set up etc. So, I would be comfortable with .15 competitive. My estimating program says, .1 for a 1 gang plastic box and .11 for a 2 gang. Again, I don't do Residential, but I probably would adjust that if I was doing it regularly.
