During the Launchpad program you retain control over your listing and prices. But some sellers have complained that the Buy Box is suppressed if they set their prices too high, and that Amazon makes them give frequent discounts which really hurt their margins.
googletag.cmd.push(function() {
googletag.display("content-ad-2");
});
So, officially you are in charge of pricing, but at the same time you may run into problems if your prices are unrealistic compared to Amazon customer expectations, and the pricing of similar products.