“I did not prep the house for inspection!”
First, you have to remember what the inspection is for: It's for you and the buyer to know what needs fixing in the house. You can’t “pass” or “fail” an inspection, and it is for your benefit as much as it is for the buyer.
If you know that major parts in the house such as the roof or the floor are not in good condition, do take note in your agreement that you are going to have it fixed, whether it's you or the buyer who will shoulder the expenses. Though in most cases, it’s the seller who pays for major fixtures.
However, that doesn’t mean that you can just leave the house that you’re selling as is! There are several things you can do to prepare for inspection without even spending. For one, make sure that your pets are secured and not running around the house. Also make sure that utilities are on, and that your lights bulbs are all working properly. Ensure that there are no locks on gates and doors that need to be accessed, namely the doors to your attic, crawl space, etc. Remove the panel cover from the electrical panel and the furnace cover from the furnace, as these need to be checked. And lastly, make sure that remote controls for amenities could be easily identified (suggestion: label them) so that inspectors know which one is for which.
Inspectors prefer that the owner of the house is not inside of it while they conduct the inspection, so you need to do these things mentioned in order to make sure that the process goes smoothly for them.