If you try to find a "one size fits all" strategy, you will lose out on so many opportunities that it will take you longer to get on that ship around the world. 

I don't think a population size correlates to quality tenants, unless by quality you mean high paying?

However, I read somewhere that a full sized shower cubicle instead of a shower bath is considered “3/4th” Bath.

Lot size: 9,365 House size: 760sqft (2bed 1 bath)Zoned: R2 for Duplex Owned Free and Clear Possibly have to fix foundationI have already contacted an architect to give me an idea about pricing but I had a few questions before I send him info. 1) how do I determine what size I would want the duplex to be. - based on other duplexes around?

To me, it seems to make more sense to use a flat number since repairs don’t seem like they’d cost more in a 1000 sqft home that rents for $1800 than one of the same size that rents for $1200.

Those data points would be the size of the property (each unit breakdown, what current rents are, what you are putting down, is there any other income on the property, how much maintenance/repairs need to be done, etc.) 

3 Bedrooms could be 800 SQFT or 8,000 SQFT, might want to give a bit more detail about the size and type of carpet you have a quote for 2K for.That said, we never ever ever use carpet if it can be avoided. 

Probably could see around $70,000-120,000 profit depending on location and what size of home.

It comes predesigned to record everything you need to enter for a rental portfolio (unlike quickbooks which is more of a mid-sized enterprise level accounting software).

It can take time and not every company is the perfect one size fits all fit.