If you bought it using a credit (not debit) card then there's also a shot that you have purchase protection benefits that include price protection and compensation for you if a retailer refuses to accept a returned product.

If your card doesn't have those things -- or ESPECIALLY if you're using a Debit card -- this is a good time to learn that debit cards are awful and you should be adding a good go-to credit card.

Any basic Visa Signature card will be a good start, but I'd suggest finding a Signature card that adds in better price protection. Some that come to mind:

* Fidelity 1.5% cashback Amex offered by FIA (aka Bank of America)

* Chase British Airways card -- includes 100,000 bonus miles, very nearly enough to fly first class from SFO to CDG, a $10,000 fare.

* Just about any American Express card -- unless you travel and want the access to airport lounges, the Blue card is often best. Get the variant that best matches your circumstances.

There are many others, but that's a good start. For pure cashback (a little unsure of the Signature benefits):

* Barclays' Priceline-branded card recently changed their rewards. It's a straight 2% cashback card now which is fantastic. And you get a card with Shatner on it.

* NASA federal credit union has a great 2% cashback card, too. It's changed recently and I'm not totally sure of the details but the last I checked it was 2% after you spent a preset amount each year. You can join by becoming a member of, IIRC, the Stargazers society.

Basic, no-benefits credit cards are silly -- get a good one! It's easy! But debit cards are evil. Friends don't let friends use debit cards.

Also, anecdotally, Capital One doesn't seem to grow as reliably with you as other cards. That is, more people get a $5k citi, chase, amex, etc, that grows to $25k than happens with Capital One. It's not unheard of, but generally the accepted consensus is that Capital One doesn't grow as easily.