Hey Supasta33,
Thanks for the post. The type of wood foundation you are talking about is usually around $400 for king size. That’s funny “$400 for a pallet seems outrageous”…which I would totally make a comment like this over many traditional box springs, but these wooden slat foundations are entirely different.
If you are using a bunkie board instead of a non flexing foundation then as long as the bunkie board is strong enough to support the mattress and the people sleeping on it and the support surface is suitable for your mattress then there is really no difference between using a bunkie board, a low profile foundation, a regular foundation, or a platform bed other than the height of your sleeping surface.
Regarding bunkie boards, If your bunkie board has a solid support surface instead of a slatted support surface then it can limit the airflow under the mattress which can be a risk factor in some environments (see post #10here ) and I would tend to prefer a slatted support surface unless there is a compelling reason not to.
There is more about choosing a bunkie board in post #4 here and in post #4 here.
Thanks for the post, let us know if you have any other questions.
Sensei