Visa/moving help

Thank you for offering any knowledge in advance. I'm finding hard to navigate and different answers every where I look.

But my story is a 25yo male with a pension of $1836 (USD) and a rental property (paid for) that brings in $750 (USD) for a total of $2536 (USD). I have a fiancé 24yo female with no income once we depart. We currently have small cash savings around $5000 (USD) and growing and a vast amount of gold and silver( I assume to be worthless for this process due to proving its monetary value but would prefer not to cash out and leave in the U.S. for a safety net/fall back if we decide to come back). And we're currently debt free.

I need to know if one, we have enough money to get a temp visa?
Two, If I can consider her a dependent as a fiancé?
And three, if $2500 (USD) can allow a young thrifty couple to live a comfortable life in Mexico for a couple of years with plans on getting into the tourism business at a later point (possibly dive/snorkel charter).

Thanks in advance for any help you can give. I can gladly give more information.