My car heater only works on full blast, (which I don't really care about so I don't want to pay 130 dollars to get it fixed) but it also only blows out the pannel and won't switch to defrost or to blow out by my feet either. What parts do I need to fix it? And how can my friend (mechanic/good with cars type friend) fix it?

When I called a mechanic they said it would cost money to get it looked at and it could cost up to 500 dollars if they have to take apart the pannel... I'm in college and DO NOT want to pay a lot to get this fixed. I just want to be able to defrost my windows!

Thanks!!!