The card I recommend currently for 0% on purchases is the
American Express Blue Card. At the time I'm writing this (so it may have changed) they are offering
0% APR for up to 15 months on purchases, which is virtually unheard of with every other creditor. The card has no annual fee and right now the other comparable cards are offering only 6 months 0% APR. Another benefit is American Express tends to give generous credit limits which would be important in a situation such as this.
If you have a big purchase you need to carry as a balance for a year I'd check it out.
Here is our review for the Blue Cash card.