What action can I take against retailer/manufacturer for defective product

There is no general 3 day right to cancel a sale except in door to door sales where you buy something at your home and even then, not always. For retail sales at a store, your return rights depend on the store's policy, which should either be printed on the receipt or on a sign posted at the store. If there is nothing said, then there is no right of return, other than if the seller gave you a warranty. As long as the seller deals in goods of the kind you bought, such as your hobby store selling car kits, then generally if the sales receipt does not disclaim "implied warranties" then you would automatically get a warranty of merchantability, which basically means that the seller automatically gives you a promise that the item will work and is safe. If it isn't then in most states you would have the legal rght to either sue for damages or cancel the sale if the product is in basically the same condition as it was when you bought it and you can offer it back. That's called breach of warranty and you should talk to a warranty lawyer near you about what your state laws say. You may be able to sue in your local Small Claims Court and not even need a lawyer. Call your local attorney bar association and ask for a referral to a consumer law lawyer or warranty law lawyer, but don't delay because for every legal right you have, there is only a limited amount of time before your rights run out and the time limit is different from state to state.