I am currently in the process of purchasing my first duplex and the property comes with an inground pool.

Sunny,Yes as long as the other party is not considered "disqualified" by the IRS you can create a partnership.The partnership can be in the form of TIC (Tenants in common, both of you will be on the title of the property) or you can create a new entity where both your IRA and the other partner can be the members. 

I just hired a lady now too to do my direct mail, $10/hr but I had to drop it to $5 cuz I can't afford the training required, which I've stipulated can only work if she can get it by so many hrs(30-50) otherwise she'd have to wait til I get someone on the kitchen/baths to get decent pay or continue going to the labor pool and she's living on a friend's couch and just told me on her way out if she can't figure it out she's going to -I don't even want to say it.

No pool.  

As the properties get redeemed, the pool gets smaller. 

I've seen Private Investors pool money where their friends cash out of IRAs, 401k, Annuities, incurring penalties to fund loans for borrowers who suddenly go MIA on the day of loan funding!

I have very much considered this.... our plan is more of a modest pool house.   

They have an advantage because they have the labor pool and the systems & connections to achieve economy of scale and efficiency so they can make a profit. 

Some say residential you get long term financing and bigger buyer pool and commercial is limited for resale.For a mainly residential investor that does not have the commercial network I could see why they think that way.

Rates will vary for policies based on age of the buildings and locations.The better policy rates tend to be in insurance pools of certain buildings.