I pride myself on design and usability of my projects. At times a 1 to 2 day extention might be needed but the end result is always worth the wait.
Here's an idea of the design of the project to fit it's needs, feel free to contact me for any questions or concerns.
I can create a MySQL database with two tables, one with products, and one with locations assuming locations will be reused.
Allow you to enter items in to the database with the following fields (assumed currently): Item name, Description, Location Name, Item's URL, and Price.
Allow you to enter locations in to the database with the following fields (assumed currently): Location Name, Address1, Address2, City, State, Zip, Country, Website, Phone Number.
And have the Items pull from the location table so the location info doesn't need to be done again.
Then develop a search for the product names, The search will have a wild-card, or a match anything between spaces. Upon finding a list of matching items, display the items sorted by name, and price.
Create checkboxes beside the items to save to compare.
Two Buttons under and above the search results to save and compare items. The 'compare' button will bring up the same result page with only the listed items saved and checked. and the 'save' will save the checked items to compare until they close their browser.
The search result would be just a list of items in a top-down list. consisting of Item Name, price, and location. with a pop-up link on the name on the Item to the item's URL. and a checkbox to the left side, in the middle of the information in a table.