This partner would get “dividend” in form of rent and then 50% of the value of the property for a min holding period of 10years.

You need to make sure the policy/coverage you get is designed for this use and not a standard homeownes policy.The Lawyer and the town can give you an idea of the Modifications you may be required to make due to:- ADA compliance- Fire Code Compliance- other Laws/Ordiances that may be triggered when you move away from a Residential to a Commercial exposure

I wanted to invest for the long term-like buy and hold.

Just getting into real estate and was wondering about if it is a good idea to wholesale. use the money as down payments and take those properties and set them up as lease option?

If the constant turn-over bothers you, but you like the idea of rental income - maybe the long term rental is the way to go.  

A follow up question I had was, does the tittle and deed need to be 50% in each partnership name ( 1031 investors and new investors) or can a new joint partnership be created with each group as 50% each owner to hold the property?

You would of course not deplete all of your cash reserves on the down payment in order to service the monthly debt payment and carrying costs, but this should give you an idea of what you can accomplish now if the time is right.Many hard money products offer 100% funding for rehab costs so you would not need to save for this portion of the BRRRR project.

I've done flips, BRRRRs and buy and hold in the LTR  and MTR spaces.

I like the idea of dealing with just one person and having them manage all the trades.

Or does the WY statutory trust hold the property as it is?