With the big kids, I used all of the crib blankets people gave me at the showers, lol.
With ds2 I'm using
these, which I bought for the birth and then washed fresh and snowy white again with hydrogen peroxide. ds2 and I both sleep nekkie-butt on my best sheets and the pads handle both blood and pee just fine so spit up and leaky breasts or diapers shouldn't be a problem.