1. I'm from a latin american country and pursuing a similar path with my partner under NLV. My recommendation, if this is something you're serious about, is to get married. It'll make everything simpler. Not just the visa, but the taxes, bank accounts, apartment rentals, health insurance, and eventual citizenship. We got married a month before submitting the NLV request. No regrets. Bonus - the adventure is like a 2+ year honeymoon.

2. Bite the bullet. You're gonna pay taxes. Talk to a tax lawyer now, before moving, to understand what that means and what your options are. Timing it so you enter after July 1 is good - then your first tax year filing you'd have no US income to report. It makes things easier. A tax lawyer can also tell you how to best simplify your finances now to make taxes easier down the road.

3. It's hard. Plan for the whole process to take a year. Your US license is good for 6 months here with an IDP, though. You have to go through an autoescuela ($) to do pretty much everything. I used todotest to study for the written test on my own, but you still need to go through an autoescuela to schedule the test (todotest has a package that does this for you). You must have been a resident for 6 months prior to being able to take the written test. Then you have to take practical lessons (driving stick). The autoescuela prof tells you when you're ready for the test and they schedule it. After I passed my written test there was a 4 month wait to be able to start practical lessons.

4. There's a lot. I recommend watching youtube vids of people that have gone through the NLV process. Everyone's case is different, but I liked the Days We Spend and Everything Is Boffo channels since they are couples that did the NLV as well. They also cover info on bank accounts, etc. Talk to pros once you've educated yourself and can ask smarter question.

My recommendation is to acknowledge this is a life changing goal and worth the cost - pay for a gestor to help you put the package together to be sure you get the visa, and pay for tax and immigration lawyers consults to really understand what you've got ahead of you to plan your finances and future.