For example we opened buy/sell agency from being exclusive to portfolio clients now open to all.

Someone in this thread mentioned the 121 exclusion.

In AZ we look off market deals almost exclusively.

We found a newspaper from 1889 in the house and also a dead cat. 

At the bare minimum, you should do the following to make your bookkeeping easier:Dedicate one checking account and credit card exclusively to real estate.

Living in the property for two years likely allowed you to claim the capital gains exclusion... up to $250K for singles or $500K if married.

I only give them a short time (usually 5 days total from the contract to hold) to meet for the lease signing before they lose their exclusive rights to the unit, so this prevents someone from dragging their feet after they've signed the contract to hold.Once the lease is signed, I take down the ads and send out emails to people in mid-marketing flow letting them know that the apartment has been rented but I will reach out if something falls through.

.- Do I qualify for for a section 121 exclusion sense I lived on the property for the first 2 years of ownership?

I'll send my off market or wholesale deals to non-exclusive buyers but only after my VIP list of buyers/investors have had a first look and decided to pass.

Again, depends on how you're planning to use the property (exclusively investment, blended occupancy/rental, or full-time occupancy) - if investment only an LLC would be the move.