Looking to develop a website that can extend the saved searches list within eBay UK

Currently ebay only allows 200 saved search terms or part numbers and give emailed notifications when new auctions are listed for those saved searches, i need to be able to save 1000’s of part numbers that would all give an email notification when an auction goes live with said part number or term, there is a site called Flippa.net that does this but only allows 20 saved searches, this would be for eBay UK site only, auctions ONLY. I am looking to have a site built where i can add 1000's of items and get emailed notifications of new auctions as they go live for the UK site only - can this be done and what would be the limitations in terms of how many saved items can be scanned? is there a limit on how much information can be checked within the ebay data available?