Startup Idea: Retail Price Aggregator for Resellers

Startup idea to develop an app that collects pricing data from all major retailers so users can reference it when pricing their items for resale. This would help ensure the proposed price is reasonable and prevent the user from being unfairly undercut.

i think theirs a problem when you are trying to sell an item somewhere but cant find avg base price to sell the item for. i think there should be a app that collects all the data from all big retailers to this app so when youre about to make ad on craigslist or offerup etc that you know itll be a reasonable price and you have proof to a seller that its a good deal and honerable price and not be lowballed from others and get ripped off.