Feasibility of adding a slide out to 4 Winds 21RB

In our group, there are a number that have added slides. Slides were not available when our coaches were built. they all cost 10~15K and most have been a reliability and water leak night mare. One was very expensive and when the shop that did the design and install could not make it work and stop leaking, they actually offered to take it out at no cost to the owner and that is what happened.

Matt