A potential renter contacted me through two services.

[David1273]

Hello:

My very first inquiry through Airbnb contacted me through VRBO also. How do we deal with this situation? 

[Tim-and-Holly0]

@David1273:

It is not unusual for people to use multiple services when researching trips. Contact them back through both services as both will monitor your response time. Enjoy the booking wherever it may come from!