Costco's policies can save or cost you real money, and most people never read past the checkout line. Here are seven rules straight from Costco's own site, so you know what you're actually entitled to.

Cancel your membership for a full refund

If you're not happy with your membership, Costco will cancel it and refund the fee at any time — no time limit. what Costco says: We will cancel and refund your membership fee at any time

Most items can be returned, no deadline

Costco backs almost everything it sells with a satisfaction guarantee and doesn't set a fixed return window outside a short list of exceptions. what Costco says: We guarantee your satisfaction on every product we sell,

Electronics have a 90-day return limit

TVs, computers, tablets, and major appliances are the exception — return them within 90 days of delivery or you're out of luck. what Costco says: Costco will accept returns within 90 days

Cigarettes and alcohol may not be returnable

This depends on where you live — Costco won't take these back in states where returning them is against the law. what Costco says: does not accept returns on cigarettes or alcohol where prohibited by law

Ask for a price adjustment within 30 days

If something you bought on Costco.com drops in price within 30 days, you can request the difference back. Costco can say no, so treat this as a request, not a guarantee. what Costco says: reduce in price within 30 days of the date of purchase

Tires come with a 60-month road-hazard warranty

Every tire bought at Costco is covered for 60 months from purchase, with prorated credit toward a replacement if a road hazard takes it out. what Costco says: This warranty is valid for 60 months from the date of purchase

Stop auto-renewal 72 hours ahead to avoid the charge

To keep Costco from charging your card for another year, turn off auto-renewal at least 72 hours before your renewal month starts. what Costco says: cancel your auto renewal at least 72 hours prior to the first

Policies change, so use the links above to check what's current before you count on any of this.