I have a product set up with a base price of $1000. It also has one option which adds an additional $100 if selected. So far it works fine when you buy it with or without the option (i.e. $1000 for item without option, and $1100 for item with option).

If I put the item on sale 50% off a problem exists.

If I buy the item without the option it works fine. It charges $500.
If I buy the item with the option It charges $600 instead of $550.

The optional part is not being discounted by 50%.

I tried using the "priced by attribute" option and then the sale doesn't work at all.

I also tried using the attribute flags in every combination and they don't fix my problem either.

I assume I am just missing something obvious and you guys can help me out.

Thanks,
Megan