You tell the client that you inspected it before and that since whatever time has elapsed you cannot sell the same report as it was purchased by someone else and the condition of the home may have changed.
You handle it as a normal inspection. These inspections I have found, sometimes take longer than the original so don't cut your price. And don't offer the name of your past client without their permission.
The broker on the last one will try to get in on it so warn them not to release the past report.