For example, you may find that he is simply using a "factor" to ballpark these costs, which he has winnowed down to near perfection over time.   

The whole 20% down or pay PMI thing is not even a factor for cheaper properties.

@Maria Crenshaw too many words and you’re coming off as a landlord that would be difficult to work with.Your credit score requirement leaves the door open to potential tenants that you may not want based on some other the other requirements.If you haven’t yet, do the research on what is usually the acceptable percentage of rent to income in your area.Everything will come to the light in the background check, so let that be the deciding factor, you’re potentially pushing away great tenants

Two high level main factors are market and operator.

Is this a limiting factor for me since the city location is not the biggest factor?

You do need to take the "appreciating market" factor out if you are planning to sell it after rehab.

PRICE is the determining factor in your market. 

View report*This link comes directly from our calculators, based on information input by the member who posted.The repairs I have considers and their factors are as follows:Possibly Roof (due to recent hurricane in the area in 2018)Water Heater (over life-expectancy)Appliances (over life-expectancy)HVAC (over life-expectancy)Flooring (they look terrible in the pictures and not long lasting)PaintCabinet/CountersLanscapingSeptic System Replacement/Cleaning

It was rebuilt with contractors, so I imagine it's up to code and it looks great, I'm just looking for the x-factor here.

You Google "how to grow my sphere of influence" and that will give you some guidance.