Looking to subdivide and build

[Gustavo Munoz Castro]

Hey folks. I own a rental property in Seattle (unincorporated King County technically) and it has a 10,454 sqft lot, zoned R18. There is a home on there currently with a huge back yard surrounded by larger multifamily properties. The previous owner started the subdivision process but went under after the crash. With rental properties as scarce as they are in King County, I'd like to see if its feasible to build some new rentals in the backyard. I'm a total noob at new construction, so I asked a friend that has done it and she pointed me to ASPI surveyors and land planners. I'd also need a construction loan to get this off the ground. Does one actually need an architect to make this happen? My friend said since its small multifamily then no. Has anyone gone through this process? I'd love some tips and recommendations for contractors and lenders. Also, am I doing this in the right order? Land planner, then bank and then contractor? Thanks in advance.