Hiya and congratulations!
We got married abroad, although not in Mexico so I am unsure on their rules. We went to Canada as we wanted somewhere where it is legal to get married outside and somewhere that does the ceremony in English and we decided that Canada was the best option for us.
We decided whereabout we wanted to get married first and then we found and employed a local wedding organiser, she did all the paperwork and legal bits and bobs for us as well as finding someone to conduct the ceremony and a photographer. She sent us short lists and we chose from those. She would have done way more but we were only having a small wedding and we didn't need flowers (took my own), a reception, cars etc. We could have done it all ourselves but it was much easier this way and for the piece of mind that it would be done right and be legal we went with her. You can also do all this through a travel agent but I couldn't see anywhere that provided what we wanted, they tend to want you to spent the whole holiday there and take a wedding package and we wanted to do our own thing, drive about and book our own accommodation etc.
With regard to guests I think it depends a bit what you want to do. Going though a travel agent you can usually book out a load of rooms and get a slightly better deal, or even go with one that offers a free wedding with so many guests. As we went independent and only had 3 guests we didn't do it that way, just let our guests know the location and day of the wedding then we left it totally up to them to choose and book what they wanted to do. Also depends on whether or not you wish to pay for your guests. Personally if I was invited to a wedding abroad I wouldn't expect the bride and groom to pay for my flights or room but I know some people do.
We had lots of moaning about our choice being selfish and inconsiderate and causing lots of hassle too so do expect that! I would not book anything on behalf of other people as if they drop out you could be left with a big bill if they decided not to pay you. Choose what you want to do then give people the details is easiest in my opinion.
We would do the same again without a doubt. We also had a big UK reception several weeks later so all the people who we didn't invite/couldn't come abroad could still celebrate with us. Best of both worlds
