A truck is personal property and would not become yours simply because it's on a piece of real estate that you bought. 

If I made any substantial additions to it, I would be happy to share it with the community and give credit to the person who made the original.

The wifi is what will allow you to access the door remotely.If you don't want wifi on it, Then you can still get a smart lock you'll just need to pre-program several different codes into it, and then give out those codes appropriately but you'd need to be on site at the door itself to program initially or update it.From personal experience I find the touch screen or wifi locks to be complete POS's that are not reliable and the battery does not last long.  

The person you sold to would probably have a cause for legal action.However, in Austin, @T.

You could volunteer as a front desk person on weekends and then gradually work your way up into an assistant while you work on your license... 

From my understanding it might have to be a personal loan, which is very expensive. 

Pay off HELCO, REPEAT.If you are an accredited investor I can discuss some Alternative investments I am personally looking at to generate income that offer tax advantages to shelter some income.

Personally prefer SFR..Not sure about DFW but do have a realtor reference for you..be sure to budget for furniture and furnishings if not sold turn-key..a seller concession is a great way to preserve capital for MTR or STR's..check in with @Joseph Chiofalo for an investor friendly lender..he's excellent at helping structure loan programs for investments.

Do they need me to go into any virtual/in-person meetings?

My thoughts below are just as a person who lived in Spain for 5 months without buying any properties in the area.Based on my initial views, it is hard to make the numbers work in Spain on a LTR.