I would get an attorney or title company involved to create your loan documents to ensure they comply with the law and cover all the aspects you need.Another method that is likely your best bet to take on investors is to create a joint venture (JV).

Currently the lot is too small within the current U-TU-B zoning.

kept using people who don't do real estate to do my taxes, and also they had horrible communication skills, I don't trust people who only see u as money.

Any tips on managing joint ownership or deciding to hold or sell would be greatly appreciated. 

I file jointly with my wife who's a w2 employee.

I am under contract for a 3 family home w a very unique set up. 2- 1 bedroom apartments and 3 and 4th duplex which has 5 bedrooms but only 1 bathroom this home is 8 min from Brown University in RI and 10 min from Johnson Wales. (6miles)Do u think its close enough to attract college students especially the duplex? 

The house is registered with my name and my younger brother’s name as joint tenant.

Here is a solid example you can adapt for a joint venture (there are differences, beyond just nomenclature, for a partnership and a joint venture): https://templatelab.com/joint-venture-agreement/Again, I would caution use of this document without a professional to review it.

The parties will jointly appoint an acceptable mediator and will share equally in the cost of such mediation.

Quote from @Tanner Pile: Quote from @Rob U.: I’m considering a flip on a land lease.