I have a 2003 Santa Fe GLS with 116K. Although oil levels seemed fine, I've been experiencing a burnt oil smell from under the hood for some time. Brought it in to dealer for routine maintenance and had them check it out, they claim that both the front & rear valve cover gaskets are leaking. I went ahead & had them replace the front valve gasket as I didnt want oil in my alternator, but the rear one is double the cost due to labor, so I skipped it. Is this possible to have both leaking? Can I wait a while to have rear one repaired and do the spark plugs at the same time? What is a reasonable cost for this vehicle? Appreciate any advice!