When I speak to finance institutions, I am only offered non-conventional loans for investment properties which require high down payments and significantly higher interest rates.

I'd recommend speaking to a referred lender to help you understand all of your options.

They understand that there's value in what they provide, which is steady, documented income, minimal turnover, steady payment, quality references, no drama, and peace of mind.

A quality deal you have control (under contract, seller only wants to work with you, etc.)3.) 

Are there any mentor/coach/investor types who know the Collin County, Texas area on this forum to speak with? 

I think their general stance is going to be to go with whichever comparable property has the greatest degree of similarity in terms of (probably, in this order): location, age built, quality of construction/current condition, and square footage.

A lot of people will pay $1200/nt for 4 crappy budget motel 6 quality rooms at the All-Star resort rather than $175/nt for an 8br themed out mansion with a private pool, theater, and $30,000 arcade room.To answer your original question on investing over a long-term period, that is really this market's main strength. 

This is also part software sort of speak, it gets updated with new features...there is work to it, idk if that labor required is intrinsic too maybe.

Under bidding, poor quality, not following timelines - those will all kill your project.

Prioritize cities aligning with goals while considering quality of life.Good luck!