Depending on local municipal development processes, some land developers upload their "grade slips" / "lot grade certificates" to LotWorks, and allow builders to download them directly, provided certain criteria are met.
Most systems with grade certificate release requirements, base them on:
1. Architectural Approval, and
2. Receipt of 2nd Deposit.
Both conditions must be met before a grade slip is released, and available for download. Mousing over the file in the Documents section of a lot will reveal this same information in a tooltip.