The quote
Does the quote cost anything, or lock me in?
No. The reach-out, the mockup, the on-site visit and the written quote are all free, and none of them commits you to anything. The quote is good for 15 days and it is yours to keep whether you go ahead or not.
An install date is agreed only once the written quote is in front of you, and it is confirmed before any money changes hands. There is no minimum job: a short run quotes its real arithmetic.