Where can you get a copy of an installation invoice from a Lowe's center?

Simply contact the store where you made your original purchase. Provide them with as much information as you can recall about the transaction (including time, date, etc.) and they should be able to call it up in their system. As a last resort, if you paid by credit card, contact your credit card company and tell them that you don't recognize the charge. A dispute file will be opened and the store will be required to provide a copy of a signed invoice within 30 days. Good luck!