Drone Orthomosaic Survey for Land Subdivision Planning

We are a land development firm preparing a 42-acre parcel of undeveloped rural land for subdivision into individual building lots, and we need a mobile drone operator to fly a complete aerial mapping mission before our surveyor and civil engineer begin lot layout. The flight must follow a programmed grid pattern (double-grid cross-hatch preferred) at a ground sample distance of roughly 1.5-2 cm/pixel, with 75% frontal overlap and 65% side overlap, flown at a consistent altitude to keep the whole parcel in one calibrated dataset. Ground control points marked with visible targets near the existing corner monuments should be logged with a survey-grade GNSS unit so the finished map ties into our legal boundary coordinates rather than floating in an arbitrary local grid. From the raw imagery we need a stitched orthomosaic covering the entire parcel plus a 20-meter buffer past the fence line, delivered as a georeferenced GeoTIFF, along with a digital surface model and a bare-earth digital elevation model so our engineer can generate 1-foot contour intervals for drainage and grading studies. Please also render a contour line file in DXF or shapefile format that our CAD software can import directly for lot layout. A separate KML or shapefile boundary overlay showing where the existing monuments and fence lines sit relative to the orthomosaic will help the surveying team confirm the corners before staking. We would also like a handful of oblique reference photos of the access road frontage and any drainage swales visible from the air, useful for early conversations with the planning department. Turnaround: raw flights within the first few days, processed GIS deliverables package (orthomosaic, DSM, DEM, contours, boundary overlay, oblique photos) within the agreed window. Please describe your drone platform, ground sample distance capability, GCP workflow, and the mapping software you use for orthomosaic and elevation processing.