hi, kea,
when I was having problems carrying more than 1 pot(I use a stick and have mobility issues with my hands), I asked Ray to rig something up like a tea trolley, a box on the bottom for compost and a tray with sides on the top for plant pots, also had to be able to be pulled with 1 hand and not too heavy
he jigged around with a truck he had, screwed a plastic box on the bottom and a mesh plastic tray on the top,he used a handle from another truck for me, result, a rather rickety but very useful 'tea trolley' I can pull easily with 1 hand, means I don't get frustrated not being able to carry a trayful of plant pots ;D
what things does he have problems using?, especially being left handed and 7'tall, something we all take for granted, hope he can find something ;D