The fact that you’ve also seen the benefits of rental property firsthand through your father is a huge advantage—you already understand that it's not just about passive income, but about management, long-term thinking, and building wealth steadily.Since you're familiar with analyzing risk and returns from traditional investments, transitioning to real estate can be as analytical as you're used to—cash flow, cap rate, CoCROI, equity growth—all of it maps well to your skill set.

You may have an advantage since there is very low deal volume in your area, and may have multiple bidders.Good luckGino

It’s important to consider where the properties are located and where the Series LLC will be doing business.The primary advantage of using a Series LLC is the ease and efficiency with which you can create individual "series" (or "cells") within the master LLC, each functioning as a separate entity without the need to file separate LLCs with the state.

This implies there is motive to minimize cash flow if it can be realized in a tax advantaged form.  

Possible advantage of S corp is net profit can be distributed as dividends without corp level taxation as S corp is a pass thru entity.  

It’s easy to get swept up in the thrill of sourcing and closing deals, but without a strong foundation in these areas, your growth may be at risk.An effective tax strategy helps you optimize deductions, leverage advantageous tax structures, and retain more of your earnings.

There are tons of options out there for consumer business purposes financing that you can take advantage of.

Is there a difference and what are the advantages?

You may want them to sell the property to take advantage of section 121 exclusion.Otherwise if they gift you the property, your basis would be their basis and you may end up paying more in tax in this situation.It is better for all 3 parties(you, uncle and aunt) to talk to a tax accountant before proceeding.

I'm not sure what AZ has incentive wise but in Los Angeles because there's a housing shortage there are some incentives that you can take advantage of like...CalHFA ADU Grant ProgramThe California Housing Finance Agency (CalHFA) offers grants up to $40,000 to cover pre-development costs such as architectural plans, permits, and utility connections.