How large are the banners that are trailed behind small planes for advertising?
Pre-911 I towed banners, and towed them with a C172 and a C182.  Parasitic drag of the banner is the limiting factor.  We had different letters, and for the C-172, the letters were about 1.5 meter block letters, during the spring and fall, when the temps were below 20C about 18 to 22 letters was the max. Climb performance in the 172 was about 150 FPM.  In hot weather, up to about 40C, the max was about 12 letters with the C172.  The C182 could handle longer banners, and was used the most during the summer.

The weight of a 20 character banner was about 135 pounds.  The banners are made up by a crew on the ground, and then hooked on a low pass over an area adjacent to the runway.  Similarly, a low pass would be made to drop the banner.

The letters we used the most were red synthetic rip-stop fabric, and they were repaired with a sail / parachute sewing machine.  Later, just before 9-11, we got White / Black letters which were out a spun fabric like Tyvek. The banner business died in 2001 due to 9-11, with TFRs (Temporary Flight Restrictions) over major sporting events. NFL did not like banners being towed near games, and the emergence of TFRs effectively blocked banner towing.

FWIW, banner towing is more risky than glider towing, even though the gliders weigh more, they have less drag. (Although I used different aircraft for each.)  Also if a letter tears, or gets loose, the flapping and increased drag can substantially impact the drag, and climb performance.