In Florida the Preliminary Notice is due within 45 days of first furnishing labor or materials for all parties who did not contract with the owner. I would like a bit of clarification to apply this to our business. After we receive a purchase order and deposit, we have to go to the property, which is typically a hotel, to field measure the windows included in the order. It is these measures that we use to fabricate the product in our factory. This field measure is typically built into the price of the total purchase order. Do we use the first date of field measure as the date for first furnishing materials or the date that we start installing materials at the property?