You can set up custom expiration dates for each quote you send.
To do so, from the Manage Quote page, click the radio button next to “Quote expires” and then click the date field.
Once set, the customer will see the expiration date in the email they receive about the quote, as well as on the quote detail page.
Once the quote expires, the customer will not be able to accept the quote and complete checkout.
Two Scheduled Tasks are automatically created when the Manage Quotes module is installed.
Sent Expired Quote Emails: Notifies the customer when their quote expires. This email is enabled by default.
Send Quote Reminder Emails: This sends the customer an email every X days until the quote expires. This task is disabled by default so you will have to turn it on if you want to use it. The settings for it are located on the Quote Configuration tab under Utilities. The default setting is every 10 days.