ADU Tacoma, WA

I am building an ADU in my backyard. The site has been looked at by the city and all my setbacks etc. look good. I need a set of blueprints for the cities approval. Because it is a small house and I have a basic plan for the house I don't want to pay much. The city is being very accommodating because they want more affordable housing in the city. I will need someone willing to make modifications based on the cities requests for changes to the plan. It is to sit on a foundation, not a slab.