Specifically, if the original loan recipient has a total VA loan entitlement of $750,000, does my assuming their $370,000 mortgage reduce their available entitlement to only $380,000 for future use?

what area are you specifically interested in?

They say to themselves, "Well, I gave it a few years; I guess this industry isn't for me..."

I think it does make a ton of sense to look around DFW than right inside DFW.And yes, I would try a few different tools to get a rent estimate, not just Zillow:https://www.rentometer.com/https://www.biggerpockets.com/insights/property-searches/newhttps://www.neighborhoodscout.com/Neighborhood Scout has pretty good info on what returns look like for specific markets.

They tried three times to get my mailing list to the correct area   I had just moved to a new market and was very specific where I wanted to mail my postcards.

I'm not sure the specifics of that market but my initial gut reaction would be that 90+ day stays may be a bit too limiting to make an MTR worth it. 90 days could work well with the average 13 weeks for travel nurse contracts but may limit your digital nomads, business traveler, etc bookings.

I absolutely detest the fact that the insurance industry has decided that the way to sell their insurance products is to disguise insurance salespeople as “financial advisors”.  

I don't have any specific goals set yet.

Smaller industrial properties have maintainedimpressive occupancy rates and rising rents for several years, and in recentmonths they have increasingly stood out as one of the best-performingcategories of commercial real estate.To learn which U.S. markets have the most acuteshortages of smaller industrial space, CoStar ranked the 60 largest U.S.markets based on the composite scores of three criteria: current availabilityrates for industrial buildings smaller than 50,000 square feet; the mediannumber of months on the market of 10,000-25,000-square-foot industrial spacesleased in the past 12 months; and the median number of months on the market ofindustrial spaces smaller than 10,000 square feet leased in the past 12 months.

A diverse set of locales comprise the 20 markets withthe highest availability rates and leasing times for small industrial spaces.The four largest Texas markets, Austin, Dallas-Fort Worth, Houston and SanAntonio, all rank in this group.However, most of these 20 markets with higheravailability rates and longer leasing timelines than most locales still havelimited inventories of small industrial spaces available for lease.