Buying the Lomo Diana F+ camera?

There's a lot of these on eBay "used once only". How bad does something have to be for the owner to get rid after one set of results? Also on eBay you will see lots opf cheap plastic cameras NOT selling at 99p or 99c depending on where you are. These are just as good as the Diana. That means $5 including delivery for the camera and $195 to spend on film and processing. If the camera's results turn out too sharp you can always scratch the lens a bit.