Spent a few years in residential mower repair.
The problem is that you can't write a ticket big enough to make $$$ with out the customer wanting to scrap it and buy a new one.
You need a big customer base for those little jobs to pay off.
Put 2 spindles and a OEM belt on most residential mowers and you double it's value.
I remember the first decent sized job I priced out after switching to auto repair, after years in the OPE repair. Standing there with a $550 dollar estimate was just weird.... I'd never written a ticket that big. Previously, anything over a few hundred meant the customer would be making a trip to Sears or WalMart for a new one.