I could never get PXE to work. Was a PITA.
I always found it easier to keep a spare SSD around as a temp install drive, along with a basic Windows PC (with a large SSD data drive) with an available SATA port. The modern setup for whenever someone drops off their computer:
1. Remove their boot drive, plug it directly into the SATA port, clone it to an image (SATA HDD to SATA SSD = fastest copy available), and run some HD tests to make sure there's nothing failing on it physically
2. While that's going, install the spare SSD as a temporary boot drive & install Windows (via USB 3.0 SSD enclosure with an ISO emulator), Office, Microsoft Updates (you can cheat & use BatchPatch or a virtualized WSUS server with the non-domain distribution hack), software, tweaks, etc.
3. Once finished, clone the golden image so you have a copy for future reinstalls (because people are always screwing up their PC & it'll save reinstall time next time they drop it off). Restore the golden clone to their stock boot drive & drop their old HDD image to their desktop so they can access their old files.
And if possible, convince them to buy an SSD for their boot drive, haha.