What do modern companies look for in a web design and development company when purchasing a web design or marketing campaign?

I will speak from my experience selling websites and what I perceive the desired outcomes from a website build: 1) Design quality (customers in the real work often value this less i.e. are happy enough with a lower quality design) but I believe that I you do this right it can have a marked impact to conversion and perception when being sold to etc. 2) Customer service / account management How nice is the person who they mainly deal with, do they set realistic expectations and communicate if any delays. 3) Speed to get it going / built How responsive for questions / update requests. 4) Price I think this is a core driver for most people which can be a shame to not have more time to make a more remarkable site. --- I would add what I wish there was more desire for is things like: 1) SEO Many clients neglect this or don't see that this is a different thing to design 2) Responsive design