A few things as an idea:
1. Make sure it comes with parts like the stock air box (just incase).
2. Check all of the regular stuff like panel colours matching, gaps around doors, boots, bonnets.
3. Check the interior, boot trim etc.
4. The rest would all be in the drive I guess. Check what boost its running (there was no mention of a boost controller). The SAFC2 I assume is sorting out any richness.
5. Check it service history if u can.