Please sign the agreement electronically or it may delay processing. Washington Vendor Agreement Template is a legal document.Make payments in a timely manner to the vendor on behalf of eligible households for the term of this agreement. 4. To become a vendor with the City of Federal Way, complete a New Vendor Form and fax to 253-835-2509 or mail to the address below. Federal Way City Hall Vendor Contracts: Blanket Purchase Order (BPO), Executed contact where there can be multiple purchase orders for the same goods and services. Please fill out and return to the Office of Vendor Relations when your company's electronic payment information has changed. To do business with Cowlitz County you will need to fill out the supplier form below. Download and fill out the form then return it upon completion. Download and fill out the form then return it upon completion.