I would contribute all or a portion of the down-payment and my name would be on the deed.

Hello All, I'm ready to BRRRR my first property and after reading the BRRRR book I want to ensure I have the refinancing portion sorted before purchasing. 

If you rent a car, you can deduct only the business-use portion for the expenses.Meals and lodging.https://www.irs.gov/taxtopics/tc511 

Start going to Real Estate Investing meet ups and networking with people that are doing what you want to do.A great first property to buy is one that you live in and rent out a portion.

Is it possible to buy someone’s garage or portion of their land and purchase it?

Things such as property taxes and insurance will have a material difference, as will the utility situation and whether or not you are responsible for any portion of them. 

With the renting portion, I'm planning on using a rental company to rent out the house while I'm away from the area, at the expected %10 rate.

While you're living in one of the units you'll have the benefit of others paying a portion or all of your note. 

The first part amounts to a variation personal loan, in which I’d be best to choose an option based on his goals-either provide a lower rate of return paying intetest only until we sell, or a true short term loan with a competitive rate.The second would be a true partner, in which case the only skin in the game for him is the portion of the down payment.

A variety of factors have increased prices including a strong economy, limited inventory, and probably as much as the previous factors - management companies lowering their splits and a large portion of buyers self managing.When management companies are lowering their splits and owners self manage it enables them to pay higher prices and obtain similar/better returns.