Can I create a coupon that will be good for one time use for 50% off any one item?

I think the answer is no,

I can setup the coupon to restrict to a spefice category or item(s)

I can setup percentage off, but if they buy say, 5 items it is 50% off all five not the first one.

I can setup the coupon to not be resticted and only used once per user.. but I can't restrict the quantity to be 1 each and be 50% off?