When using normal FHA or 203K FHA on foreclosures owned by private lenders (WF, CHASE, BoA, etc.) if there are multiple offers yours will likely get pushed aside because they would rather work with buyers not needing to renegotiate price based on appraisal. Of course if you are the only offer made on the property they will likely take it. But i have not seen many foreclosures that are not in multiple offer situations.
My advise is once you find the home you are interested to purchase consult with your mortgage broker if the PROPERTY will qualify for any of the loans mentioned above.