Quote from @Michael Smythe: @Kwanza P.Recommend exploring as many sources as possible to get referrals AND cross-reference them to get as much accurate information as possible.Check out NARPM.com, BP’s Property Manager Finder (BiggerPockets: The Real Estate Investing Social Network), etc.Also, encourage you to learn from the mistakes of others - by reading posts here on BiggerPockets about owners not having their expectations met by their current Property Management Company.

Have you ever filled out an maintenance/cap ex spreadsheet with expected lifespan and expected replacement costs to try to accurately estimate sustained maintenance/cap ex.I already know you did not accurately project increased insurance costs. 

Inside, examine the structure for water damage or cracks, test the plumbing for leaks and good water pressure, and check electrical systems and outlets.

Seems interesting run a split test see if it works out for you.

It's a very expensive repair (ballpark $15,000) and the cost depends on how long the sewer line is.A lot of municipalities here require dye tests and occupancy inspections.

I know it's hard to accurately estimate w/out seeing the house.

Make sure your assumptions are accurate before you make the purchase. 

The truth is you can never get it "accurate" as the actual numbers will fluctuate year to year.

Since you have a noise monitor you may be able to use a decibel reading which is the objective measure to determine a legitimate complaint provided you can get it to accurately record the louder noises.

There are always opportunity on the MLS....properties that are listed/categorized incorrectly....properties that rely on public record square footage that is not accurate but the broker is too lazy to verify and simply relies on the autofill data, properties that have base zoning that allows for a better use, properties with unique characteristics that are not properly detailed in the marketing information, properties that are simply listed over priced and become stale and are good negotiation opportunities.