Renegotiating a Fannie Mae Homepath Property

I currently have a Fannie Mae Home Path home under contract. I got the house for well below market value and just needs some minor rehab work. However during the home inspection, the inspector found some foundation issues and a major plumping issue. Neither of these items are going to make the deal bad, but it will be a little more money out of pocket. In order to cover some of these costs can I renegotiate the contract price? Has anyone had any experience in this area. Any help is appreciated.