For immigrant visa, you have business related visas, special visas, and family related visas. I assume you have no path to the latter two. You have the option of the infamous EB-5, but also the EB-1/2/3 (which are apparently quite difficult to get and require a US employer petitioner…some of these are the US “residency by exception” equivalent).
There are also non-immigrant visa that can allow for adjustment of status to permanent residence. The H1B is the infamous one, but there are some explicit ones like the K-series (family based) where the intent of the visa is a single entry followed by filing an adjustment of status or some where you can adjust through a convoluted strategy like the L series or E-1/2 (temporary business visas). B visas are generally not convertible and you’re almost guaranteed to run into trouble using an ESTA for long term repeated visits. A man from the UK who I know was nearly denied entry at the airport after a two month visit and then attempting to reenter a month later. It’s up to the discretion of the CBP officer you encounter.
I’ve helped one person get a convertible visa, helped two people get B visas, and given some advice/watched about half a dozen others go through their processes in getting immigrant or nonimmigrant visas.
The process can be a bit arbitrary both in the US-side USCIS/NVC processing and, in a different way, in the consular processing (US consulates have a mix of American and local employees and tend to take on the “business characteristics” of the nation in which they are located). Wait times are long for most visas (B visas will be about six months unless your consulate is very busy…others take much longer) and anything with a quota and priority date can be over a year to years to complete. The process and decisions are a bit arbitrary and very opaque. There are ways to get through the automated phone tree and Emma app to speak to a real person that were shared with me by a sleazy
immigration lawyer I use for such things, but even then getting information is difficult. You do want the sleaziest, most “Better Call Saul” style immigration lawyer you can find if you choose to use one. I know of two, one in Miami and one in the midwest, who have been helpful to me. They’ll be able to abuse the process in many ways at little to no risk to you.
You’ll be in the
US tax system quickly if you do anything to trigger the
IRS residence tests (green card or substantial presence test) and there is some complexity around first year choice and dual status tax status for the first year you trigger that. It is a bit easier to get out of the tax system compared to being a citizen once you decide to leave, though.
Legal compliance is a bit of a mess. You do have access to US
investments and banks but overseas
FATCA starts to bite as they view you as a US person due to residence. In practice as a
US citizen, so far, this hasn’t been a problem for me yet and I’ve been able to bank and transfer money with no problem. I only ran into one problem transferring money to Serbia which was resolved quickly. That has been a bit overstated in my experience. If you get dragged into the US tax system, you do run into
CFC and PFIC issues and compliance costs as well.
As far as grey or black areas go to avoid triggering residency or high cost, you can try visa or ESTA runs and you might get lucky for a while. It takes one bad encounter at passport control to get black listed so it’s not low risk. I’ve heard of people having more success with this using temporary multi-entry visas than ESTAs. An overstay will likely get you flagged the minute you leave and try to reenter as the airlines generate I-94s for their departing passengers automatically now. Neither of these are recommended due to the limitations they impose.