Treat your tenants with the utmost of respect.

Won’t I get killed with taxes at the end of the year if I make, say 100k from these properties since they’ll be treated as short term?

If you go in with guns blazing with all sorts of demands and treat the seller with suspicion, you're setting negotiations off on the wrong foot. 

People definitely treat you differently when they know you can close deals effectively, but since you don't have a big track record yet my bet is that the people you're running into have a similar experience level as you do. they can't help you, you can't help them.

@Cherrell Thomas cash flow is the profit that's left after debt service, property taxes, property management, common utilities (if any), reserves for repairs (small things like leaky faucets, AC servicing, etc), and capital expenditures or capEx (larger things like a new roof,new HVAC, major plumbing overhaul...these are treated differently on taxes, written off over a specified longer period) and other expenses.The first item I mentioned, debt service, is where the answer to your question is.

We've found they often attract a stronger resident/people will treat them with care & stay longer as it feels like they have their own home. 

The sale of the land to the entity can be treated as sale of the investment property.

Eventually we knew we had to treat this like a flip to get our money back and try and move to a better area for our family  We had torn out old flooring, I cut out and replaced some rotten subfloor next to doors.

Not exactly:If you moved out in 09-14 and you move back in now, until 09-19, that year up until 09-14 drops off as it wouldn’t be within 5 years.Also, since you lost the 121 exemption in 09-17, if you moved back in for the 2 years you’d need, you wouldn’t get the full exemption.....it would be prorated based on the number of years you did occupy verses those you didn't.In your case, at 09-20, it would be about a 2/3 exemption (8 years verses 4).Also important, the 121 exclusion only applies to the Half you lived in.....the other half is treated like an investment property.You’re also going to have depreciation recapture on the other half, plus your half while it was a rental.  

Most of my business is repeat and referral so my best advice is always treat your clients right, put them first, and learn to ask them for referrals and you’ll do great!