My long-term goal would be to earn passive income through real estate to the point where I could cut back to part time at my job, while still having the financial freedom to travel and enjoy life. 

You've either raised rents by rehabbing the property or putting rents to market rent, or, you've cut down expenses somehow. 

You want a place for cutting, keeping tools, etc. without worrying about stepping over things or getting your personal items dusty.Hire contractors with good recommendations.  

Not sure it's the route I will go as I'm thinking I'll probably invest locally but it does sound like it cuts through some of that stuff you described.

I've seen a lot of folks start cutting corners when they get over budget. 2000 for AC is awesome, just signed with a guy for 3800 for a single wide MH unit and was tickled. got some estimates as high as $10K. 

Can you partner with the neighbor somehow to make it their benefit also - like installing two new drain fields or connecting to the City sewer together to cut cost?

For instance, the shiplap in the bathroom pictured above is just CDX plywood with a saw cut every 8".

Feel free to cut and paste in browser since I can't figure out how to get to work....https://www.texasrealestate.com/uploads/files/general-files/2016TexasRealEstateYearInReview.pdf

It can be stressful on a marriage if you're not on the same page.Tip...I got a flexible part time job as a substitute teacher...So, if I wasn't working on an extensive rehab, I worked at the school...In the beginning, I painted, cut grass and purchased all material to save $$$...If it's your Desire to do RE and you're 100% committed,  your husband will probably honor that...GL

My concern is my rental income will be more this year so I would prefer to right off on a larger income year to cut taxes owed down.