Db Schema Recommendations?

[tangledcords]

I am having trouble with a relationship in my FM Db. I have a car detailing business with multiple locations. Each location has it's own set of available services. It is also possible for an appointment to have multiple services. My problem is with the relationship between location and services. I have attached a screenshot of my schema. I want two drop-down list controls on the Appointment layout. The first is for location which will then dynamically generate the second drop-down which should be the list of available services for that location.

I understand the basic concept of how to implement this within FM, but my current schema is not setup correctly (as you will see). I have been told I need an additional TO of Services, but I'm not sure how to implement this exactly. Again, I want to use drop-down controls for both fields. Also, if you notice the CarModel/CarMake/modelsValueList in my schema it is a similar setup where a Make drop-down drives the Model drop-down and it works well.

Any help would be greatly appreciated. Thanks in advance.

Schema.pdf

[comment]

I meant something like this:

ServicesAtLocations.fp7.zip

[tangledcords]

Thanks once again for your help. I came to this forum so I could upload the schema. I figured a picture is worth a thousand words, right? I was getting confused in the other thread about the checkboxes you mentioned.

However, what you have provided here makes sense. I hope to get a chance to try to implement these changes tonight.

Thanks again!