5 biggest mistakes an owner-occupant makes

If you own commercial real estate you either occupy the buildings with your company as an owner-occupant or you rely on a tenant (investor) and their rent.
I have clients that are both owner occupants and investors — they own the building from which their company operates AND they own additional commercial real estate which is leased and provides a nice income to supplement their day job.
With that differentiation as a benchmark, I want to describe the biggest mistakes I’ve seen