Bill customers an upfront fee if they do not have a membership account

I have appointments + and membership working together. I created membership tiers and found the thread where you can limit the number of appointments based on their membership plan.

Is there a way to also setup appointments+ to bill customers an upfront fee if they do not have a membership account?

Basically I want to book appointments for customers that pay membership fees; and book appointments for customers that do not but charge them a drop-in rate?

All appointments are basically remote house visits. The pricing model loosely follows this example.

Silver paying members get one house visit per week. Additional visits require a service fee

Gold paying members get two house visits per week. Additional visits require a service fee

Non-paying members are charged a service fee upfront.

Is there a way to follow this model and if so what additional plugins should I install, and can you point me in the right direction on how to setup?
More details on this model here: http://devsite.gasbutlers.com/residential/

Thanks!