problems with a purchase

[2010audain]

I bought a scooter. The seller contacted me to say he sent the wron item. He said I could have this different item but I said I did not want this. I wanted what I ordered. He asked me to refuse it when the delivery came. I am not at my house and told him I might not be able to do this if it arrived when I was out. He then asked me to return it. I agreed to do so but only if this did not involve waiting in for pick ups. He cannot send the correct item till beyond next week. So I decided after many e-mails that enough is enough and I just want to order my daughters scooter elsewhere. Now he says I have to deal with e-bay but it is not possible because it just goes straigt back to requesting from him. He says the scooter has arraived but it has not. I am dismayed to discover the payment has already gone from my pay pal account and there seems to be no way to get it put back. How can the seller keep my money when by his own admission even if the scooter does turn up it would be the wrong one and have to go back anyway?