Help w/ buying a large lot, permitting, building SFHs, potential sub-division

[Gabriel Fung]

I am looking to moving to the East Seattle area, specifically Redmond, Sammamish, and Issaquah over the next few years.

The plan is to purchase a large lot and develop multiple single-family homes. One for my primary residence, and the others to either rent, or potentially subdivide and sell. 

I am lost on where to start and would like expert help with the process.
- How do I know/confirm how much of the lot can be developed (i.e. sometimes the lots are steep slopes or swamp lands)
- How do I develop with the potential to subdivide to separate single family home lots?
- Which permits will I need and what is the process to follow?
- Any construction companies and project managers that frequently do this type of work in this area? 
... Many other blind spots that I recognize I haven't figured out yet.

For context, I currently live in California (Bay Area) and plan to sell my home here, as well as my investment property in Dallas, TX to fund the purchase of the land and all costs associated with building out a multiple homes in the area above. 

Any advice and connections anyone can provide? Please and thank you :)

Sincerely,

Gabe