That is, sometimes an agent and seller with lower the fee to the agent when the property is tough to sell.This is a strong list but it is not exhaustive.

I had a brand new AC put in (May 2024), first guest after snapped the condensation pipe pulled the drain pan clear out.  

Just to confirm I check the exhaust flue, it is warm and getting hot.  

In my experience, many insurers will cover the house but not the roof, ensuring you have protection against fires, broken water pipes, falling down the stairs, etc.

We tried to get an extension so that we could get an inspector to scope the pipes but the seller wouldn't grant that extension.

I'm curious to hear from the experienced folks - finding the right property at below-market value for BRRRR seems very exhaustive, wouldn't they be more motivated to sell a property at market value for less work and more profit?

I don't believe DSCR would be the right way for you to go on this until you've exhausted all of your conventional options (and I'm a DSCR broker/lender).  

The water pipes are filled with awful moldy smell so you smell worse after you shower.

They brought in a "plumber", said the house had multiple leaks in the pipes, needed re-piping and concrete broken up to fix the second leak.

I also include large sewer costs if piping material is clay or cast iron.