It is common practice in the Plantation Shutter Industry that both the buyer and seller sign a written contract outlining the mutual obligations of both parties at the time of purchase.

I cant stress how important it is to make certain you read your contract before signing it or handing over any of your hard earned cash.  It does not really matter what your salesperson has told you, or even written down.  The contract that you sign is generally binding and will normally state that it supersedes anything else promised to you. 

It is common practice in the plantation shutter industry for the seller to offer a lifetime warranty as part of the sales pitch to entice customers to make a purchase.  A lifetime warranty is usually a guarantee on the lifetime of the product, and not the consumer.  If it is a limited lifetime warranty then the limit generally does not allow the consumer to transfer the warranty to someone else.  They say the devil is in the details, and with shutter contracts it isnt any different.  You will likely have a list of items outlined in the fine print that will void the warranty.

And last but not least, if the shutter company flat lines and goes out of business, then your lifetime warranty is dead.

In conclusion,  any promises of lifetime warranties should be outlined in a written contract, and are only as good as the company that is offering it.