Should I use something like propstream to find all acreage that fits my size parameters then just start doing drive-bys to see if it looks like it would work?

If you can find a 'prefinished slab' company, you should be able to get a regular size kitchen done in granite/quartz for <$2000.IMHO, it is worth it and can justify a rent increase.

Long story short, they recommend a process that basically looks like...Soil scientist --> (septic engineer IF needed) --> site plan --> county approval...We've spoken to a few soil scientists and they all quote 2k-5k to analyze the property for an appropriately sized septic system. 

I expect to grow to that size eventually, but that day is not today. 

This is not a one size fits all game - everyone is different.

If you knowingly rented a home with a small backyard to a tenant with a dog, regardless the size of the dog, wear and tear is going to come into play.  

Make the large primary photo your backyard pool, and include the room with the king size bed, in the primary photo collage.

San Marcos is known for its college town vibe, potentially offering a broader rental market and the size of this one could be a good student rental.

There are plenty of older homes on the market that do not have closets.You need 2 egresses (including 1 that goes outside) such as a door or window, size about 70sqft (local codes may differ), ceilings at least 7ft high, and it cannot be a walk-through passage.As always, your local codes may be different.

Upstate New York will generally qualify with standard markets such as Travelers, Nationwide etc... there are a few other property programs that do very well depending on the size.