What do I do with eggs when both parents are dead?

Both my finch birds have recently died, most likely from sickness. They left behind 8 eggs, one egg cracked. So now I have 7 eggs, and I'm thinking of trying to keep them warm myself. However, incubators are expensive-I don't have $500+ to buy one, especially since I'm saving up for college. What should I do with the eggs? A friend of mines suggested I just throw them out. Right now I've placed them on a bed of cottons with a lamp shining over it. What do I do?! I loved my birds, I want abandonment to be the last resort. Or should I not worry because it's too late for me to help them now?