- install live feed camera- smart locks to monitor entry times- get friendly with next door neighbor and let them know to send you complaints or contact you if there seems to be an issue- always have written approval before any change orders- perhaps a % of contingency can be applied as a bonus if they complete the job ahead of schedule.- let them know you will pay them within 48hrs and have a signed w9 before any payment is made. - does GC have 2-3 subs in each category as backups- will they work on weekends if behind schedule?

If one wanted to take security further one could put video surveillance in that area that is motion detected, posted online for the renter with text notification.