Fred me and my friend took on this task last September! You have to register the right way when you enter every country! I forget what it is called something to do with entering the northern border and exiting through the southern, if not you will have to turn around and drive back through Mexico to get the proper stamps. When pulled a trailer behind a 2007 Jeep Commander, transmigrante is what it is called when you go through the borders(very important), and with hauling anything through Mexico or any other county you have to go through a transmigrate service where they inventory everything you are hauling. We had a list of what we had inside so they just copied the list. It was like $700 to get that done. They also xrayed our truck and trailer, for guns and children. Know your Spanish! Have all the ltitle for your car if yours has a loan you wont be able to take it. At each border they will try and get you to take a "guide" through the country, they will tell you have to do it! That is bs just bribe the the people and be on your way, in spanish tell they just want money so here it is. Unless you don't speak spanish then it might be beneficial to you. Each country gets cheaper as you go down, but Know Spanish! We drove 30 straight hours through Mexico! We were warned by security gaurds that they hear gun shots at night at the border and blah blah. The roads are fine all the way through don't worry about that. Worry about the shifty individuals at the border crossings. It cost $1500 for the 45 minute drive through Honduras, we got taken for a ride, but after sitting there for 8 hours we were ready to do what ever to get the hell out of that dirty place, and we were stopped on four separate occasions, not including passing a stop where the cop car sitting there had no wheels and cutting through a gas station to avoid another one. Most of the stops they were just curious to what in the hell we were doing. Through that brief stretch most times we heard the word venti, by the guys with machine guns. Which is give me 20 dollars! have bribe money in a separate pocket from your wallet of cash because once they see how much money you have they will want it all! No matter what you situation you will be seen as as rich gringo. No problems at any other borders but those two! Do not trust anyone! Know some Spanish! We made this trip in about 4 and a half days! Not much sleep in there when we did rest was when our things were locked behind a gate and a couple naps of the side of the road in the middle of no where. When you get into most gas stations they take credit cards, but not all of them try not to exchange money at every border unless you plan on hanging out in the country! but you will need pasos in southern Mexico and gautamalan money. In Nicaragua I got back dollars for change. Didnt need to exchange money in El Salvador I dont think. Just get the hell through Honduras use the southern border patrol it is open 24 hours although has long lines and is slow, but they do take dollars there too. I have read not to hang out in border towns and only cross borders before 1 o'clock so you don't get stuck there waiting in line after dark. It can be done my friend. We had a masonic symbol painted on the back of our trailer, you may laugh or smirk, the polica will be a lot cooler, the are all masons! Really man learn a beginners mason hand shake and have a something that displays that you are one. Every cop with dealt with commented on it! Don't talk a lot your brother is one and you are just joined! We estimated over 12 hours of wait time that was cut off our trip for preferentially treatment. We had a Mexican stop an exit line and had his officers move barrels so we could turn around and he told us he takes care of his brothers. You have no idea of the unneeded preparation we had made for this trip. I would recommend having a good supply of water. You have any questions just shoot them back to me.