Roof-Mounted attic fan

Roof-mounted attic fan at the car wash?  The smaller unit is for 1650 sq. ft. and 1170 cfm for $53.82 and the larger is 2100 sq. ft. and 1500 cfm is $110.

Today, it was 98 outside according to my weep mizer and a thermometer about two or three feet from the roof says it was about 95 inside.

There is already a hole in the roof for the boiler and the fan needs a 14 1/2" hole cut.  Would this really help with the heat?