The other way depends on how fast we can get cleaners arranged, get it back up on the market, shown and re-rented.

Call drain cleaner and ask them what it costs to snake a drain.

RE cleaners: ask around locally to other owners.

This industry is full of surprises and you did well to extend the benefit of the doubt to the landlord (they probably did not intend to give you such a dirty place and it does stink for all parties involved when anyone cheats and lies to another, like when the cleaners and make-ready teams do this). 

We are gearing up to purchase another property in the next year or two and are debating....do another one in the same area, as we already have cleaners/contractors/services that we trust?

I schedule my cleaner in between stays, have handymen as needed, locksmiths, etc.

It’s cleaner on your Title chain and saves you one closing if you go through with a full closing to potentially keep your Title Insurance, etc.As a new LLC it will be tough.

Its cleaner if you do it when starting the LLC, but even later is basically capitalizing your LLC or an owner contribution. 

I have strong credit and would be able cover the costs in the case the rental situation doesn't come to fruition, however where I am hung up is #1 - comping out properties in these more rural areas where there is lower volume and inventory to compare on a $/sqft basis let alone if the information is available and #2 - the majority of the properties I am looking at are older (built 1960s-1980s) some have cosmetic renovations but likely still old bones..this brings me to the my final point is building your 'team' I how have others found reliable inspectors, handymen, emergency services contractors, even cleaners for rental properties?

Personally I like the PnL method because it is cleaner and easier than 12-24 months of bank statements.