Seen on eBay, a MacBook Pro PVT at a vastly overpriced rate.
A PVT prototype is essentially identical to commercial models, as PVT stands for Product Verification Testing. In Apple’s case, PVT models are not particularly rare for a good reason: some PVT Macs occasionally make their way into the market. A typical example is the iBook G3, where PVT-marked motherboards are relatively easy to find because Apple used them in retail units (for reasons unknown).
As for this MacBook Pro, it’s a 2008 model (the last one before the Unibody design). It hasn’t been tested—which generally implies « does not work » —and apart from the marking, there are no specific indications that it is a prototype. For example, it’s unclear whether the motherboard is red. Furthermore, this Mac is likely dead, if only because it features a notoriously unreliable graphics card. So, €800 for this model seems way too much in my opinion.