I also have all sellers do inspections on their own homes. We use the clean inspections as part of our marketing.
Even from a financing perspective, in dealing with clients we always recommend the inspection. (I scratch my head in a bit of confusion when I see clients who do not exercise that.) In fact, on an FHA loan as part of the mortgage documents (HUD-92564-CN) it is required that we issue this doc...For Your Protection: Get a Home Inspection.
I'd say darn near close to 100%. The only exceptions would perhaps be during the times when the market was REALLY hot hot hot and some buyers wanted to win in a multiple offer situation, so they'd submit an offer not contingent on the inspection. But, usually, they'd have the inspection, just not make their purchase subject to those findings.
I strongly encourage them to have one, I personally had an offer on a property that we found 25,000 plus in needed repairs that we missed when we looked at the property. It is worth every penny, but make sure you have a good inspector and call their refrences, there is not much worse than paying for a worthless inspection.