An extension normally continues at the contract rate or a stated holdover rate, but availability, notice rules and scheduled pickup can affect whether the unit may remain.
Read the extension clause before the initial term
Confirm required notice, new billing period, rate changes and whether the extension renews automatically. Ask whether the supplier can commit the unit elsewhere before your decision deadline.
Compare the same office and site scope.
Give every supplier the real ZIP, use, size range, term, delivery date and setup responsibilities.
Update site permissions and services
A longer placement may affect permits, utility agreements, tank service, maintenance and insurance. Extend those items with the trailer rather than assuming the original dates remain valid.
Notify the provider as soon as the schedule changes
Early notice provides more choices and reduces rushed pickup disputes. Include a realistic overrun range when comparing mobile office lease pricing at the beginning of the project.
Turn this answer into a useful supplier comparison
Record the decision that applies to the property, who owns it and when it must be complete. Connect that note to the proposed unit, delivery plan, access equipment, utilities, service and removal so an unanswered assumption does not return later as a change in price or schedule.