Landuse Restrictions in Washington State

So here I am, searching for a larger parcel to build a lifetime homestead on... and I keep running into comparatively inexpensive properties with massive Wetland Buffer Zones and other semi-arbitrary restrictions and I'm trying to wrap my head around exactly what I'm allowed to do, and what I am not.

If anyone has any experience in this field, any advice would be greatly appreciated.

[Also, what does one have to do to prevent an man-made wetland as one might create for growing food from becoming protected?]