A reserve price is the minimum price the seller will accept. This price is hidden from bidders. To win, a bidder must have the highest bid and have met or exceeded the reserve price.
Once you completed the checkout, you will not be able to combine additional auctions. No exceptions.
All payments are expected within 7 days after the last winning auction is closed.
Bidding on multiple auctions? Simply wait until all of the auctions are ended. Complete the checkout via eBay's checkout, all winning auctions will appear in one screen.