I’m going to help them replace some things since my uncle has a shop and I have the knowledge. It’s a 2000 Nissan Maxima SE. I was hoping not to charge but exchange work for work, how much would you charge if they got the parts for an oil change, I’ll provide oil, knock sensor, drivers side cv boot, and front and rear catalytic converters. Perhaps an 02 sensor. You think asking 600 in trade is too much?