You're spot on about security deposits being a practical tool to mitigate risk, especially with applicants who have checkered rental histories.

There will be competitors in your market that offer viable housing options, so how do you capture these valuable contracts?

I think I am on a path to recovery, ready to check out the market tools to finally pick and market and find some deals!

If you really don't value your agent's ability and think you can do it better, it's likely best that you 1) interview more to find one that you do trust, 2) go through the listing agent, directly, if you're that comfortable with handling your side on your own, or 3) maybe get your license so you can control your side of negotiations with the proper tools needed (MLS access with agent info, showings, contracts, tax records, uploaded listing docs like surveys, disclosures, broker assistance for questions, etc.).

BP has various tools to help you analyze your deals (rentals, flips, wholesale, etc). : https://www.biggerpockets.com/investment-calculators7.

I would disagree with number 2 - in this environment, heavy rate buydowns are a common tool in the toolkit for lenders and borrowers to make deals work and are in no way indicative of "not being well-capitalized"

Conservative debt is a tool to generate higher returns and build wealth.  

For analysis, you need to identify a market that interests you using tools like AirDNA, Mashvisor, Pricelabs, etc. 

In similar situations, it may be worth considering renting first and selling later when market conditions are more favorable.Finally, the importance of choosing the right agent is a valuable lesson.

Debt is a great tool, but you have to be very careful with it.