There was a guy who went to the gunrange in Bellingham and he had the set-up I think you are looking for.

This OLD guy, must have been 40 or so ;), had bought a baby stroller at a garage sale for a few bucks. He took off the seat section and the built a gunrack section so he could haul five rifles from his truck to the shooting benches. He had a shelf built down below where he had his shooting box, insert tackle box, bungee corded to the whole set-up. He said it cost him about 4 bucks for the entire outfit, but a new umbrella stroller is only about $10 anyway. It no longer folded up, because of the modifications, but he just hauled it in the back of his truck.

A setup like this could get you down most stairs, and would make hauling that gear, plus a nice fish, a lot easier. You could customize it to fit your gear, and it would only take about 2 or three hours if you have the ability to figure it out.

I just pattented it, so if you make one, ya owe me 10 bucks.

Let us know how that goes.

Andy