I don't love the idea of giving up my sub 3% mortgage rate and paying more to borrow money, but sitting on that equity and not putting it to work makes me feel I'm leaving a lot of growth on the table.

You can make an extra several grand a year....don't leave that $$ on the table.

I would say as a GP, technology has been super helpful in managing our cap table and issuance of distributions along with making it a lot easier to streamline the process of investor signing documents and sending $.

The other option of selling the house and investing the tax free gains is also on the table.

Having a strong boots on the ground team in the area can help bring good deals to the table, filter deals better, determine viability quickly (which in a market as competitive as this is very necessary), and ultimately get the right deals done.

Now do you have a table of comparison of property appreciation in those 3 states for last 5 yrs and 10 yrs? 

He is seasoned agent but with no rehabbing experience but wants to learn and help and will bring cash to the table for the deal.

My favorite side hustle (other than rentals) is waiting tables at a fine-dining restaurant (and I am almost 50 yrs old).

What are they bringing to the table that you cant get more cheaply or for free?

If you are going to do this type of business make sure it is in an area you can visit or make yourself familiar with, you have someone that is representing YOU at the table like your Attorrney, and you don't make decisions based on "we need to wrap this up".