It's just common sense, but not really scalable as a business of its own IMO.   1.)

I think it's probably less common here but I've often wondered about how difficult it would be to convert a detached garage, etc. on a property from a legal standpoint.

One common approach is to form a legal entity, such as an LLC, where both of you are equal partners.

@Ethan Borshansky, There was a brief period of time in the early 2000s when this type of "leasehold exchange" as described above was fairly common. 

On the other hand, you might find a common reason that a few of your potential investors are not investing that might change your own thoughts on the deal.

DSCR Loan (10% Down Possible)Debt-Service Coverage Ratio (DSCR) loans are based on the rental income, not your personal income.Some lenders allow 10% down, though 15-20% is more common.6.

The great thing about living in a high cost of living area is that your salary / wages are hopefully also very high.If you are a new college grad, I would focus the next 1-3 years on increasing your salary as much as possible(gain new skills, new certifications, change employers, etc).Once you make more money, you can easily get in a position to buy a property on a more frequent basis.Best of luck!

Do you have any books or resources out there that he can dive into to help him hopefully avoids some of the common pitfalls?

They sell a 4 unit for close to 1 million dollars close to Jacksonville. they want 250k or 300k down. there's no upside. you can google the properties on biggerpockets and there isn't a lot of satisfaction. it's a slow return and get rich slow strategy. our focus is always as a builder to add maximum value, lower cost as low as possible, build and rent and build and sell the same product and raise prices to help investors out. we have a large market share and large purchasing power in our market in columbus ohio. the one strategy I never liked about turnkey new build brokerage companies like them and build2rent or others is they don't really build close to urban centers and most are single family homes. the numbers don't work on single family homes. if single family was the way to go more companies would be doing it. but by far the most common type of new construction built is three story walk up apartments.

Have you been employed as an Abstractor?