Good point; the one of interest to us had earlier been incorrectly categorized as "Normal" which the FAA since corrected to read "Restricted; aerial advertising, Other- Banner Tow, Glider Tow". The "Time and Cost" concern regarded converting this Pawnee from banner towing with Schweizer release to glider towing w/Tost release. We love our tow pilots.

.....though sometimes that's not so obvious. This summer a misplaced tow rope got sucked into our tow plane's prop. Only one tow after the engine was replaced and prop overhauled; and while towing a twin Grob (single pilot), rear canopy started to raise @ 2,500', glider nose pulls up, tow plane's tail goes vertical, rope breaks, tow plane enters spin, spin recovery but becomes inverted, tow pilot recovers at 500' AGL. Finally the tow plane and glider land safely but both front and rear glider canopies have departed (front one broke loose possibly when cockpit items shattered it when in negative g. We are so thankful the tow pilot's vast experience got him out of that mess!