Bigger blades , pump more air but need a bigger turbine to drive it. To find out exactly what the turbo is you'll need to know what the turbine size. I'd hazard a guess and say the compressor inducer is 42mm same as the k04.
Price is really hard to say, simply without proof of where it was bought, it could be a £250 cheap chinese turbo or a £600 hybrid and thus I don't think you realistically could sell it as its a huge gamble.. It may look good but without knowing its background you can say whether it is or not.