Yes they are out there they offer a low rate to come out, but end up costing you big bucks.
When you call they should answer the phone with the locksmith company name.
Hire Locally (Most local locksmiths don’t use call centers).
Ask to see a business license. Its a red flag if they don’t carry one in their vehicle.
Don’t allow them to use air wedges on houses or are quick to drill the out the lock.
If they demand cash or refuse to leave until payed cash, lock them out and call the police.