Lazybeacher has asked: "Now that you had a little fender bender, in you opinion, is it still a good idea to tow behind the motor home? Or could you manage without the toad?"
For me, the answer is simple. No, I could not do without a car. This is the advantage a truck and trailer combination has over a motorhome like ours. You can park, unhook, and you have a vehicle to get around in.
Most RV parks are not within walking distance of shopping. We use the car almost every day for picking something up at the grocery store or exploring. Several times we have abandoned the motorhome and used the car to visit nearby towns, sometimes staying in a hotel for a couple of nights in towns where motorhomes would be too large to maneuver.
Buses are sometimes an option but routes can be confusing, some are very crowded and it is very inconvenient to pack several bags of groceries on a bus. Taxis are plentiful and cheap in Mexico and that is a valid option but most are not radio controlled and cannot be called. Most RV parks are not in places where taxis regularly cruise for fares. You could end up walking many blocks waiting for an empty one to cruise by. In some places, San Miguel de Allende for example, taxis are always cruising by the RV park and when we were there we used them extensively. It was very convenient to be able to go to town and not have to worry about parking
For us, traveling in Mexico is all about exploring and we do not want to be "stuck" in an RV park. We have seen many people in this position. Some, like our Dutch friends, can pack up the camper very quickly to head out to the store or whatever. It is not a huge problem for them, but every time we mentioned to them that we were going to the store and would they like to come, they did. I am sure even they would like some form of secondary transportation, even a little motorscooter like our friend Les finally bought. It gives you freedom.
So, even with the added cost and risk of accidents, we will keep the old Honda. Yes, it is old. A 1989 Accord with 250,000 KM on it so a small unrepaired ding no longer hurts it's feelings. It is a good traveling companion and it blends right in here in Mexico so we will never be mistaken for "rich gringos" when we drive it.
There are costs involved. Insurance is required, there are four more tires to wear, road tolls are higher and it probably costs me one mile per gallon to tow it. It also makes U-turns harder to make. But, after weighing all the factors involved, the convenience of having the car outweighs the costs.