I have a 60x30 one story ranch. Based on a square
being 100 sq ft, a flat roof would be 18 squares.
Figure in 6 ft to the peak and call it less than
20 squares. Than add 4 squares because I don't
do these calcs for a living and round it up to 24
squares.

The first four estimates I got were 34, 32, 30, and
30 squares with prices ranging $5,400 to $7,500.
Not one of the estimators took out a tape or walked
the roof. Everyone of them said there was one layer
already on the roof so it was a roof-over. When I
said I wanted the roof torn off, they said it was
unnecessary and would cost an extra $1,000 to $1,200.
I knew there were two layers already on it.

A roof replacement was not an immediate need so I
waited a year. Finally someone walked the roof.
said it was 24 squares, already had two layers so
it was a tear-off, had two soft-spots which would
probably need new underlayment, made a few other
suggestions, and priced it at $4,650.

It's the difference between dealing with a roofer
and dealing with a commissioned sales person for
a roofing company.

Dick