You will need a Residential Single Family Purchase Contract (assignable or double close), then a separate assignment of contract interests.

Looking into some multi unit residential properties in the Pittsburgh area.

How different is the commercial loan process than the residential one?

Anything lower than that for a 1-4 unit residential property and you will most likely cash flow negative unless you have a large down payment (20% or more), do all your own management and maintenance (hey, I thought you wanted to be a real estate investor, not a jack of all trades handyman/property manager!) 

Seattle itself is already rather anti-landlord and getting worse every year. 

The down payment will vary by property type; perhaps 5% if it’s to be owner-occupied, 25% if residential (1-4 units), 30% if commercial...  

We work with a number of foreign investors and can introduce you to a lender that works with foreign investors for residential and commercial properties.

@Frank RobinsonCMX-3 is a community commercial mixed use property that should have residential and commercial use together. 3 unrelated people rule is per one unit, not per building.

The other lot had 22 more storage units, 2 sheds on the boundary of the second lot and a 4 unit apartment and garage on the residential street side of the lot.  

My goal is to have a team of investors with me who effectively pool money together to finance  and purchase residential homes through the LLC until selling to turn a profit.