Your parcel of land will need to account for limitations like this if you develop in the county.You will still need a permit from the county to install well and septic and these limitations will be your biggest obstacle.One other item - if you're looking to build a larger mobile home park there are sometimes drainage restrictions after you have a certain number of square feet of impermeable surface.  

I previously lived in the Portland area and am now an active investor in the Seattle area.For the Seattle area, I recommend starting with the largest groups:REAPS at www.reapsweb.com (which also has a number of interesting sub-group meetings)REIA WA at www.reiawa.comAnd then search for real estate in Seattle area on www.meetup.com. 

@Amit M.When we converted our 5-unit (now a 6-unit) from a common laundry room (2 machines w/ a third set of hookups) to en suite laundry is was motivated, in part, by a higher use for the laundry space (it and the garage are unit #6).  

He wants to buy the land for under $2.00 per square foot.

Best,Larry FInvestor Washington

I have plenty of Washington DC & Northern VA buyer! 

About three years in, he had some money troubles and fell behind on rent, but then pulled himself up and squared up.  

I'm looking at rehabbing a legal 4-unit on the north side of Chicago in a class A neighborhood (Lincoln Square / Ravenswood) and the top floor rear egress is in a bedroom, making the bedroom not a legal bedroom but, rather, an "office" or a "den".

The repairs would be 20k higher to flip. ( new windows kitchen rehab etc) Rents just are not that high in this area Spokane Wa Its a very large house 3000 sq ft.

-tvs https://www.tenantverification.com/  tvs was the service I'd use to run credit/criminal/eviction checks on prospective tenantsas for the others, a I would track a lot on spreadsheets or databases I keep. for estimating area rents, I wrote an script to pull all of the rent info for my area, parse it all by city/town and in some cases neighborhood name, then use the data on rent, square footage, and number of bedrooms to generate averages and watch trends in the rates for each area.