I created my online listing, and with the fact that my husband was going to be out of town shortly after listing it, included a time for an open house, in a week and a half. 

That would make the house into 2 rent-controlled units.If it was me, I'd rent out the entire house that includes the in-law to 1 party, 1 lease, which would make the house not rent controlled.

I think your first issue is your 25k scope of work may not have been close to reality.but it still looks like you have enough room to at least break even.there are many flippers ( myself included) that sometimes break even is a great win.flipping is fraught with risk.

Currently renting my basement out to a single mother and her child since last March, original rent was $1575 (all utilities) and I saw her situation at the time and dropped it to $1500 for a 12 month lease with all utilities included, she purchased a electric charging vehicle less than two months after moving in so obviously taking full advantage of all utilities included.Two months ago, she had a boyfriend stay with her and told me that it was temporary while he is looking for a new place.

Currently renting my basement out to a single mother and her child since last March, original rent was $1575 (all utilities) and I saw her situation at the time and dropped it to $1500 for a 12 month lease with all utilities included, she purchased a electric charging vehicle less than two months after moving in so obviously taking full advantage of all utilities included.Two months ago, she had a boyfriend stay with her and told me that it was temporary while he is looking for a new place.

@Shera GregoryOn another note, you will want to make sure the  LLC operating agreement includes language surrounding the solo 401(k) rules.

Lots of red flags including rent rolls etc. but I'm still working on it. 

I feel like many people regret any sale unless the numbers are a slam dunk (and even then I see a lot of seller remorse, myself included).

My property includes 1.08 acres of land with a water well on one corner of the property and the neighbors water well on the other corner of the property.

You will be so far ahead of so many people (including me!).