Sending smaller amounts?
Sending smaller amounts (100-200 USD) is not getting complex at all. Most of the smaller remittance companies does support and allow you to transfer $999 or less. For an amount of this range it is recommended to use RIA Money transfer and they support most of the destinations.
One major reason is that the state and the federal regulations are met easier when you send less than $999. Using Pangea could help you with sending money to Mexico. It is just because they give better rates though they have a small fee. It is always better to compare these remittance companies with USD Explorer as the calculation between exchange rates and fee can save you some money.
Usually transfers of more than $1000 are only fee free. So for a smaller amount it might always end up with a fee. So just compare with USD Explorer as it makes a lot of difference when sending money to countries like India, Mexico, Philippines, Pakistan or Bangladesh.