I just had my small (1300 sq ft) old house done. One flat roof section added to the cost. Total was $5150.
I discussed my concerns with the salesman beforehand: no leaks and NO NAILs left in my driveway and yard. He assured me that they would be very careful.
Last evening I went over the yard and driveway with my magnet and picked up
30 nails. I'm pretty sure there are more there yet.
I'm thinking of subtracting $5 for every nail from the check I write him and see what he does.