Some of these groupings were more so to reduce length than for accuracy, so please correct me where necessary.PittsburghBluff/Terrace Village/Upper Hill/OaklandAllegheny/Manchester/Central NorthsideSwissvale/Braddock Hills/RankinSummer Hill/Reserve Township/Millvale/Spring GardenIndianapolisFountain Square/Bates HendrickArsenal Heights/Woodruff Place/Willard ParkAtlantaAdams Park/Cascade Heights/AudobanBeecher Hills/Mays/West Manor/Green Forest Acres/Green Acres Valley/East Ardley Road/Mangum ManorDetroitRosedale/GrandmontGreen Acres/Sherwood Forest/Palmer Woods/Unversity District/BagleyNorth End/HamtramckSince this is my first time, I was hoping to…Understand whether these are good markets for my criteria (or if there are others I should be considering).Hear about people’s experiences in and the state of these markets.Learn about any variables that I may have not considered, either in these specific markets or as a first time buyer.

AirDNA prides itself on accuracy but doesn't estimate insurance or utilities.

That's why the calculator is more accurate for that one.I would say do some independent research by looking up similar listings on Airbnb, VRBO, FlipKey and even Craigslist, to see about prices and accuracy.

There are 1,564,537 real estate agents in the united states (didnt realize they tracked the number to this accuracy)  so i will say 1/3 no longer exist after a bad downturn. 

"To know the accuracy of the info you need transaction dates".

So, that’s what I think of using Zillow for accuracy. if for fun, or to get a ballpark deal, fine. anything beyond that, get your team built, get an agent, or investor or both to prove or disprove comps etc

Is there any advice for improving my accuracy at predicting these important numbers?

Its better to use actuals than estimates to improve the accuracy of your pro-forma.

Double check accuracy everything, and read all the T&C's on the relevant sites.

As the meter ages the cup/disc will hang up or not spin with low-flow uses, which reduces the accuracy of the meter (to your benefit).