|You would need to build the demand in your market for a service like this. If you can get customers to pay $3000/ day + expenses, you should pay for your camera quickly.
Smart-assed comments aside; you say you are in the flooring business? I believe that this sort of inspection would be most likely carried out in situations where the tiles are installed vertically. If the bond of the flooring fails, no one is likely to be killed by falling tile.
It looks like these guys have been inspecting tile jobs for a while, and probably know exactly what to look for with, or without an IR camera. The IR provides a non-destructive confirmation of their opinion. If you are already inspecting the work of other craftsmen, and your opinion is valued (people pay for your inspection), IR may be an excellent value-added service that you can provide your customers.