If you are going to sell then you must understand the tax implications. 

For context I am a full time lender and understand DTI and have very good credit. 

Don't confuse the two.You're 19, good for you to getting involved but keep it trim.

I understand I can increase liability in each individual landlord policy, but one single umbrella policy is much more cost effective when I have multiple properties.

Being a part of the local REIAs in both towns can help you understand more of what is going on.  

They also don't understand the law, or the changes that are happening around the country.

There are so many great strategies to help you scale your portfolio, so I understand your desire to find the right plan and avoid mistakes.

Instead I want to take advantage of the opportunity I have of living rent free to invest my time and money in STR's to hopefully build that portfolio up and eventually make that my main source of income (I understand that will take time).

For sure you need a lender who understands them VERY well - try connecting with @Jose Valdovinos who is here in Chicago, but lends across the country!

I know that I will need a good realtor on my team that understands not just the market but the real estate investment industry itself.