I bought almost the same car 3 years ago, N reg Polo 1.4 5 door, Dragon Green (probably just like his with metallic "sparkle") with 110k, MOT and Tax for £1000.
Even with lower mileage and slightly newer, he might struggle to get more than £800.
But as said, it's only worth as much as someone is willing to pay.
These days everyone is wanting to get something for nothing, so expect people to want to negotiate a lower price.
With ebay it's tricky, start the auction too low and it could finish with a low price after only a few bids, start too high and you may get no bids.