I have to offer this disclaimer I don't know what your overseed procedure is or the purpose, I am sure it is different than mine. We scalp he turf down to the dirt and overseed with a rye blend so we have winter grass to mow. I know other southern states do this but am unclear why someone in Jersey is overseeding in the fall.
Pricing is why documentation is so important. When I first started I went T & M and I documented every yard, time in time out, how much debris hauled away, condition of turf prior to scalp etc. After 2-3 seasons I took this information and came up with unit prices that includes the whole enchiladas. Scalp, irrigation check, overseed, dumping, spot reseeding. I have 3 prices per sq. ft. based on prior condition of the turf. I have some lawns that are like putting greens and it is very difficult to scalp them the turf is so dense. When I take over some properties the lawns are so thin the scalp takes no time at all.
BTW I still document everything. The guys fill out a worksheet on every job every time.
“If I accept you as you are, I will make you worse; however, if I treat you as though you are what you are capable of becoming, I help you become that.”