$250 + at auction. Some have hour meters and some never did. Clean retail on a used one has been around $750 - $850. They are pretty decent Civilian Grade units. One of their neat features is the #1 coil is heavy duty and the full 3kw can be taken on a single 120vac outlet. Plus they have 240 as well. They are not so common but if you are patient you will see them come up from time to time. There are not any real issues to watch out for on these units. They have a simple capacitor type voltage regulator and no speed adjustment. They run best with diesel fuel treatment, otherwise can be a little smokey on this new fuel. There have been some late model ones going for $1,250 and they should be near new condition at that price. They are one of the smoothest running single cylinder engines, practically no vibration. Noise is less than most open frame diesels but still louder than gas sets. 3kw is all they will do. The engine won't push more. The later versions with the Hatz engine are cleaner running and more responsive overall. The German Hatz engine is very high build quality. The older Subaru / Wisconsin diesel is not as crisp or as strong as the Hatz. Hatz units are going to cost more.