There is a benefit to setting up a simple webpage, facebook page, google business page, and/or small youtube channel.

There is a time and a place for a DIY cost segregation study rather than an engineered cost segregation study. 

Besides that, my taxes are relatively simple, W2 job. 

I not going to post links here... but a simple google search will pop some alternatives.I've not used the calculator here and I don't see information on what it covers or what questions it asks or what kinds of results it gives.

In reality what happens is you end up paying more for a "clean house" but because you are doing a flip people want new mechanicals (central air, 200 amp electric, pvc plumbing stack) so you end up doing a full gut or larger rehab then simple cosmetics and now your returns have shrunk.In your situation for your first investment I would be ok with a smaller return because of the experience gained, but for the next look for larger profit.

Is it as simple as move-ins and move-outs?

one simple item is framing labor. 

The 10-Unit complex would be a commercial business, so the simple answer is to purchase and operate in an LLC.

I wouldn't see an issue with this one, as long as there is a clean title should be a pretty simple process.

My recommendation is always to start with the end in mind and keeping it simple.