Advantages could be team work, gain experience working together, also financially where you are not only responsible for all expenses you can split them in half. You work together and get things done quicker and more efficient and you can also come up with great ideas together and implement them from there. However, there could be disadvantages to all of them leading to conflict which would be just the opposite of what I just mentioned. Having to work with someone, and having to deal with finances together and costs and budgets. Hope this helps a little.
