Am I simply a hobbyist because I don't charge everyone the same rate or because I left 0.25% on the table?

I never really take it serious with rent rate optimization.

I had a similar experience also didn't get 2 of my properties rented by November after I turned over one at the beginning of August and the other mid September.I switched to another local but flat rate company who rented both in less than 2 weeks.

The purchase price, loan amount, your interest rate, whether you need mortgage insurance, your homeowner's insurance cost, property taxes, and your current monthly debt obligations all factor into your DTI.  

Here are highlights of the program right from their website:Program Benefits-A 30-year fixed interest rate mortgage loan, several rates and loan options available-Down payment assistance (DPA) 3% to 5% of the loan amount-You do not have to be a first-time homebuyer-DPA provided as a grant (never needs to be repaid) or 3-year deferred forgivable second lien loan-Available statewide through a network of participating lenders.

HMLs would be able to fund the entire deal and give you money for the rehab; however, this would come at a higher interest rate (5%-12%). 

The rate jumps to 15 percent on capital gains, if their income is $47,026 to $518,900.

(Urban, suburbs, rural) What population sizes and growth rates?

I am 35 and the owner of a 1000sqft 2 bed 1 bath starter home that I bought for 150,000k in 2020 at 2.75% interest rate. 

The housing market in Corpus has cooled since last year when interest rates spiked.