If a customer is getting more than one key made at the same time, the second key should be disconnected.
I like to talk to them directly. Establish a convenient location for both of us. If all keys are lost I will evaluate the area and determine if it's a safe location before accepting the project. Once I am there I try to make the customer feel comfortable with me as much as possible.
I attended Keyman Locksmith Training and obtained certification in Automotive Locksmith, Advanced Automotive Locksmith and BMW programming to include Eprom.