Please fill out the following form completely. ("Contractor"), and the City of Chicago, a municipal.Contractors wishing to utilize the VDVNA will obtain blank Letters of Assent either from Local 134 or ECA. We'll help you craft the best vendor contract agreement for your specific needs, and help you manage that relationship as long as you need it. Instructions: FOR USE WITH ALL CONTRACTS. The Design-Builder must fill out a separate transmittal form for each submittal and include other relevant information and. Information on email method included in the form instructions. Freelance writer looking for a document or contract to cover arrangements made with a client? A Letter of Agreement may be just what you need.