I review and update my listings regularly, use all the features provided, post excellent photos, etc.

Ally You got yourself in a jam by allowing them to get by without regular payment for so long.

I had just bought an off market property to flip but didn't have a regular agent I worked with yet.

You can find out what makes the seller decide to sell by getting to know them and communicating with them regularly.

I know the city inside out and lived there for 20 years, visiting regularly.

Also, define how you'll share the acquisition costs, such as the down payment, renovation, and closing costs.Payment Responsibilities: Explain how to divide and pay for regular costs like mortgage, property taxes, insurance, homeowners association fees (if applicable), and upkeep expenses.Management and Maintenance: Agree on how property maintenance, repairs, and improvements will be handled, including decision-making processes, funding for these activities, and responsibilities for performing or managing the work.Single Decision Point: For example, I've seen situations where one person agreed to replace an appliance while another strongly opposed it.

Was able to get them all leased with regular tenants.

You'll defer all tax.For the 1031 you will use all of your regular professionals in their normal capacity. 

If you paid $300k and sell for $850k…If you owned it less than a year, $550k of regular income at full tax rates state and federal.

Try educating tenant on appliance and regular maintenance that needed, such as replacing furnace filter. and make sure communication is done properly in right format, like text messages and then follow up with call, if in need of Maintenace repair.