How can I map multiple fields to one 'parent' field? What I want to do is best illustrated with an example. 

Apartments have different price ranges for different units according to how many bedrooms/bathrooms those units have.

How could I set up a content type that will allow me to do something like this:

$500 -- 5br/4ba

$400 -- 4br/3ba

$350 -- 4br/2ba

In the above example each price range has a corresponding 'bedroom' and 'bathroom' value.
In order for this to work I need to map these price ranges to these values. Each apartment entity can have up to 10 of these mapping pairs.

I hope this makes sense. I can't figure out how to set up the content type.

Thanks for your patience and help.
See this example post on Select lists for content types:
How to have CCK &quot;Select list&quot; field on my content type?

you would just make the values for the list option as (value | display text):


500 | $500 - 5br/4ba
400 | $400 - 4br/3ba
350 | $350 - 4br/2ba
... 6 more options of whatever conditions ...
 25 | $25 - you sleep in the closet


This price field could allow up to 10 values if that's your limit.

Since the keys (values) of the prices are integers. You could SUM or Aggregate the values using Views if needed.