>Without forcing consolidation, how would one do this? Use the wildly popular technique that has taken over the assessment of everything else too big to measur

>Without forcing consolidation, how would one do this? Use the wildly popular technique that has taken over the assessment of everything else too big to measure: the random sample. Every registered technician will enter each job performed into a lottery, which will be reviewed by a qualified analyst. A single bad finding shouldn't ruin anyone, but a good record keeping methodology with appropriate sampling and a suitable penalty for failing to register a job — registration will likely be demanded by consumers anyway — should effectively weed out any laggards. I am not aware of this being implemented for any home maintenance, but this is how hospital accreditation is done. Every now and then The Joint Commission shows up and inspects stuff.