I to bought a house that had been winterized and had the same problems. However, having winterized a home myself I know that this can be very difficult to do. Since water pipes are not designed to be drains they are rarely sloped to a common drain point. Pockets of water will reside there with no tru way of removing it. In the property I purchased I made sure to turn the were prior to close and when we found the burst pipe (usually near vertical elbows) we forced the seller (mortgage company) to repair.
