If you have an issue you can raise a complaint through eBay. Check their FAQ as you have to raise the complaint case within a certain time period (might be 45 days or similar). They then contact the seller and if no resolution they will refund you usually. Hopefully the seller just bumps up their own auctions so if they sell they get the price they want so you are okay. They win auctions like the ones you listed with their dodgy account and then relist if the bids don't hit the price they want.
Just make sure you only bid up to what you want to pay, so you don't get into a fake bidding war and pay above what you should.
Good luck!