Which question can help discover a customer's needs?

Asking how old the home is and how long the customer has lived there is an effective way to uncover a customer's needs because it provides insight into the customer's environment and personal experiences. The age of a home can indicate potential pest issues; older homes might have structural vulnerabilities or a history of pest problems that newer homes might not. Additionally, understanding how long a customer has lived in the home can reveal their familiarity with any pest issues they have encountered, which can inform the solutions you offer. This question not only gathers relevant data but also opens the door for a more personalized discussion about the customer's specific situation and pest control needs.

The other options, while they may offer some relevant information, do not delve as deeply into the customer's specific circumstances. Questions about what the customer wants or how often they spray are more focused on their current practices than on understanding the broader context of their needs. Asking about affordability can inadvertently put pressure on the customer without establishing rapport or understanding their motivations for seeking pest control services.