I have purchased a third property with a partner and am actively looking for other partnerships.

I think an LLC taxed as a partnership is a better answer from a tax perspective. 

Purchase price: $4,320,000 Cash invested: $300,000 On this property I own 18.75% of the partnership.

@Julian Romo I don't have the documents in front of me, but if you do a "partnership" with those LLC docs, you should have a place to enter the members information and their % of ownership in the LLC.

Learning is the most important aspect of any formal partnership and i would love to meet fellow New Hampsherite investors!

Are you looking to establish a partnership wherein they put up the money and you do the legwork? 

Better yet, buy an owner-occupied 3-4 unit using an FHA mortgage, which allows lower down payments on 3-4 unit properties than conventional mortgages.One last thing, search here on BP for posts about structuring partnerships.

I think sometimes it is in our best interests as landlords to remember that our relationships with our tenants is not necessarily adversarial as it is a partnership.

My brother is wanting to go in on another one with me, and I am looking for some ideas from others how they may have structured a partnership in a STR deal. 

We're looking to purchase it as partners but I'm not sure what the best sort of partnership contract would look like.