Specifically, I’m interested in discussing:-Trends and opportunities in the San Antonio and Austin real estate markets-Tips for successful cosmetic renovations and cost-saving strategies-Potential partnerships or joint ventures on upcoming projectsFeel free to share your experiences, insights, or even just say hello!

@Noah Margate, if I get seller financing, I don't have that mortgage show up on my credit report, I can negotiate the interest rate with the seller, I do not require an appraisal, origination fees and other "junk" closing costs. 

To me the quadplex would be dual purpose, while you are not living there it serves as a reliable stream of income, once you move there, you could live in 1 of the units while you build your permanent home, and you could also use it for when your family comes over for large gatherings.A 2nd option might be to build an RV park, Unless their are zoning restrictions, you should be able to build one fairly inexpensive, with a septic system and either public water or a well, you can keep your costs to a minimum by doing gravel roads, which are easier to remove later if you don't want them. 

I plan to build versus buy because Im currently working for my father, who is a general contractor in Fl, and will save on the construction costs because I can do most of the work for little cost other than materials. it would be minimum labor cost and no profit cost from contractor.

Flower distribution, Power drink distribution, tortilla distribution, small tool distributor, etc. 

My biggest concern was that I have no bargaining power when its under contract on splitting repair expenses with the seller because I have to close on it.

I utilize these products but more for commercial multifamily where they build in an interest only period, 30 year amortization schedule, and the bank funds as much as 100% of the construction costs.

Adding 5th unit is likely to cost much more than value added due to worse finance options available.  

These booking are often not made by your eventual resident, but rather they may be made by some harried assistant who ultimately has the power to choose where the "VIP" stays.

If you already have a preliminary site layout showing the size and quantity of buildings you can put on the lot, you should be able to take that work on some budget construction costs and from there work your possible rents into the equation to see if what you have drawn makes sense cost wise, or if there is a more efficient way to lay the site out and reduce costs.