That depends . . .
Generally, the location is pre-determined at the time the Title/Escrow company [T/EC] sets the date, time, & location of the signing with the signers.
When accepting the Signing Order, you’re agreeing to the configuration and specifics of that order including the designated location.
Regarding our role with respect to the location: We’re meeting them to facilitate their signing at the time & location of THEIR convenience. The hiring party normally includes within the instructions that the specifics are not to be altered without initially conferring with them for approval & authorization.
NOTE: If the signers ask me to meet at a different location, I accommodate their request. 
Here is a thread that you may find insightful as well: