Splitting a Mortgage with a Partner

[Jordan Parra]

Hi! My dad and I are looking to purchase a duplex together. This would be a 75/25 split as my husband and I would be house-hacking by living in one unit while we split the other unit evenly with my dad as a short-term rental. It is move-in ready and we would be going in with a conventional load. The reason for this is that it's a large property just outside of our price range in a hot market (also, baby on the way so we are jumping through whatever hoops we have to for a property). My question is for people who have split mortgages with partners- are you able to actually take out separate mortgages, or is it one single mortgage and you work out the payments between partners? 

Additionally, how does this work with claiming it on your taxes? That is the main benefit going into for my dad on this deal.