I know from doing the HJC Fundraiser and the auction we held for 5 various signed shirts, that the items you mentioned are very, very cheap.
The jerseys we auctioned were unframed too, as they can cost around £50 to get them done properly.
I know to auction such items on a fundraising night is all about hiking the price up, but the Gerrard jersey went for about £250 I think, the Torres one around £270.
The Certificates of Authenticity should look geniune with your items, if so maybe you've been offered some real bargains. Are these items of somebody you know, or can someone vouch for the person selling them?