How big is this place? just tow the mower, its on wheels. You just need to add some kind of attachment point, so you can bungee the mower handle to the rear deck. The mower will tow on just two wheels that way. Bolt on a big gate handle and you have it made.
My schwinns had the rear basket, and I bolted a 1x4 stick to the back of the baskets. Nursery/garden wagons then just hooked up by dropping the handle on the stick. The wagons also had the stick, so you could tow two wagons at a time too.
I see no reason you could not tow a wagon with a trash can full of clippings, and the mower hooked up behind the wagon.
Just tow a wagon for any big cargo you need to tote. easy peasy. Unhooked, the wagon can also go places the bike can't, to load it up.
Bear in mind, my advice comes from 17 years working at the condo's. I tried a lot of shit, and nothing beat the trike and wagon setup. You could be working someplace with a pile of tools, materials, or green waste, and unhook the trike and zip back to the tool sheds or the bathroom when you need a tool or a pee.
