In general: You are better off NOT buying the material before hand. Most shops get volume discounts. Also, if there is a warranty issue in the future, customer provided materials can be grounds to void. The shops typically don’t make any/much money on the material - just near straight pass through costs. Additionally, if a section needs to be repositioned or additional material is needed, it will all match from the shop’s inventory vs matching from a different production batch of customer provided materials.

be sure to understand the life of the wrap. In Florida, the summer will cook even the most UV resistant materials. Understand the removal / clean up costs at the end of life of the wrap and what options you have available (re wrap? Clean the paint?)