I want to try and find a set of bigger buyer communities or larger institutions that can reliably buy 5-10 properties per month in the following states: LA, TX, MS, MO, TN, GA, OH, FL.

Get to know the agent, be friendly and professional...if the property goes on the market and doesn't sell for a while, that agent will probably call you back.You might want to send out letters/mail campaign to find your own off market deals.  

Also the rental LLC is registered in the state of California as the rental property is in California!

Yes, you can provide your own tech.

I'm not sure about other markets/states/cities etc., but here in Pittsburgh, PA I see a ton of listings marketed on Facebook.

And for the other side of the duplex you will need to state that they can do up to maybe 20 dryer loads a month. 

I believe the one good thing about that spreadsheet is that it can be adjusted by the State you live in. because costs are different in every State the estimate sheet i believe is based on a multiplier for the corresponding State, as most cost estimating books are based. that program does break down a lot of information for you and i think it is a good program, one thing you may want to check is if the program updates every year with current multipliers for the States ( program is probably based on a starting average value for each thing and then the multiplier changes as prices for materials change) and you want to make sure it does that.

My husband and I are dipping our toes into rental real estate by renting out the family home that we've been in for over 22 years.We own the home outright. 

I owned and sold/rented a few mobile homes, and somehow today I came across mods and am now binge searching all day.I'm out in Cali, and out in the inland empire land is cheap. 

They are framed and delivered to most any state.