Just a word of warning for anyone leaving Mexico and entering Belize at the Chetumal border crossing. The border officials seem to regularly collect a $20.00 US exit fee that is NOT LEGAL!!
When we reached the border we stood in line at the security booth to have our passports stamped out of Mexico. I did not expect to have to pay as we had paid to enter Mexico, and a fellow traveller had just left Mexico and entered Guatemala without paying a Mexican exit fee. My companions were ahead of me and told me there was a $20 US (or peso equivalent) exit fee that they had not expected. Skeptical, I asked a few people around the area if the fee was official. No one would tell me straight out that it was a scam, but one man said "I cannot tell you if you have to pay it or not." which I took to mean that it was a scam. I got back in line and approached the window, where I passed my receipt for the Mexican Visa and my passport through the window. The official inside then asked me for 240 pesos or 20 dollars for the exit fee. I told him I had already paid to enter and that I thought there was no fee. He handed me a very official looking blank receipt with the amount on it along with spaces for name passport etc, and insisted that it was necessary. When I continued to protest (hoping I was right, as he did have my passport) he changed his tune and asked why I couldn't pay - did I not have any money? I bluffed again, and said that I didn't, and he said that I had to write on the back of the form that I didn't have any money, and sign it. I wrote "No tengo suficiente dinero para pagar este impuesto" on the back of the form, and tried to pass it through without signing, but he insisted I sign, I did, he took it, stamped my passport, and I didn't pay the fake fee. So, if you are crossing at this border, put up a fuss at the counter, as this fee is not required, it's clearly going into someone's pocket.
Also, the Belizean border doesn't make it at all clear that you MUST HAVE Belizean insurance for your vehicle, and this is a super easy way for crooked police to extort money from you if you don't have it, so make sure to spend the $20 you saved on the Mexican exit tax scam on insurance for your bike in Belize.
Ride Safe - O.