Pricing tools that exist on the market are decent, but you also need to know how to control it, otherwise, it will go nuts with unrealistic rates far out and extreme last-minute discounts. 

I was looking in Columbus OH but the market is so saturated and it's been difficult for me to find cash-flowing deals there.

Letting your contractors (specifically if you have a GC) what the budget is and that the must notify you if a change order exists (versus they tell you after the work is completed). 

You have acquired skills that are worth 500k, so maybe you can translate that into an adjacent career path and leverage your existing skills?

The house I regret most for not getting it is this one,https://www.zillow.com/homedetails/N8064-975th-St-River-Fall...I was so close to getting it, but I chickened out because I have absolutely no idea how these houses even exist.

Could you sell 1-10 of your existing properties and reinvest in one or two more lucrative opportunities?

This policy will provide additional coverage above what your existing policy covers.

If your existing rental properties reported their financial performance on your most recent Schedule E, then your lender should be using a net cashflow analysis based on the Sched E figures for your DTI for those properties in most scenarios.

I'll be honest with you, in my experience, I have never seen a Investor care typically about the existing financing, or what was owed on the property.

Two, you'll have a much easier time obtaining a mortgage product if you have a track record of W2 income.In the meantime, continue implementing the strategies you mentioned: save religiously, build your credit, pay any existing debt owed, etc.