I live there all my life no the demographics and have owned many houses and flipped many houses there.  

The exception would be if your serving a market that caters to a student target demographic, such as near a college or senior housing target market.

I did my Demographic research on the area. 

Businesses and amenities, colleges/unis, attractions, institutions (places where tenants might work or play) and lastly demographics, are the type of ppl who reside there, people you want as tenants?

I think as @Bryan Otteson mentioned Geographically/demographically different properties count as separate income streams. if you have 20 SFH in an area, and a 20 Unit Apartment Complex in the same area, they are different streams because they are different demographically. 

So any future sale involves someone that wants two houses on a single lot, which I can see scenarios like in-laws and/or investors big on cap like me, but that limits potential buyers to a particular demographic and I also feel like it constrains appreciation.

I'd say look at demographics (change in population, employment, etc.) in those areas and, importantly, drive through them yourself, to see what you like and what's convenient for you.Also as I've recommended recently in other threads, be sure to check out the finances of any city/town you're planning to buy in, including current and historical changes in municipal bond ratings (Moody's, Fitch, etc.).

I would say that this neighborhood is 50% renovated already.We are finding that wholesalers have some deals but in C or D neighborhoods with at least a 3-5 year horizon before there is the possibility of upgrading given current demographic growth and direction.

I think Texas is the state with the most opportunity with a growing demographic of singleprofessionals, empty nesters and couples that would be thrilled to not have a high rent by living in a small house sharing community space.

I have completed several high end properties in the last year for my personal portfolio, and have shifted gears back into the middle/lower income area as this demographic is having a hard time finding quality homes that are reasonably prices.