a stainless steel film will be easy to keep clean and won't do much damge to the wall when removed. http://www.amazon.com/Instant-Appliance-Stick-Stainless-Steel/dp/B00BAUPS9M
I would encourage you to read up on SPF and if you do go that route, make sure you get a great and insured installer. SPF does have additional benefit from and air sealing standpoint but beyond the a ... read more