Device to pull a garden cart?
If I have your permission, I might make an instructable about the top answerer's idea*. If anybody has a question on instructables question, I will try my best, no doubt, to answer your question. Even after I have chosen the best answer, you can still tell me your questions and I will try to answer them until, I don't know, the end of January.
*I will put in the Instructable, if I do one, the name (screen name) of the best answerer. I will note it throughout the process of the vehicle to pull the cart.