Appliance Installation and Repair

My wife and I are trying to replace a Kenmore washing machine while stacking an older Kenmore front loading dryer on top of it in our condo. The installers from Sears would not allow us to do that due to liability concerns and compatibility. We would still like to pursue this option with a 3rd party contractor. We have purchased the washing machine. We can buy a compatible stacking kit for the washing machine if required, but we are not sure if it will match the older dryer (again, both are Kenmore brand). We also would like the old washing machine to be taken away once the new one is installed.