Yes, you could sue the owner based on fraud, which is making a material misrepresentation or lying about something important in order to induce you to do something like buying the house. Since electrical heat is more expensive than gas/propane and so less desirable, and it is essentially impossible to believe that the former owner did not know what kind of heat he had, based on what you have written, he likely did commit fraud. You could potentially recover the amount to convert to gas/propane, or possibly if it could be shown to a reasonable degree of certainty, such as with realtor expert testimony or comparables the difference between what you did pay for this house and what it would have been worth had the heat been correctly described. The litigation risk for you if you had the home inspected, and/or did a pre-closing walk through of the home, and so it can be shown that you should have discovered the heating system before buying, the you might have difficulty recovering money another element of a fraud claim is that it must have been reasonable to rely on the misrepresentation. However, if you had an independent opportunity to ascertain the actual type of heat, then it may not have been reasonable to rely on the MLS listing. If so, you might not be able to recover compensation.