I need help with a rebuild p0304 p0306

Hey everyone I’m new here.
My buddy has a very clean 04 with 208xxx. He wants to sell it because he says he has 2 misfires, and someone said the motor is no good and needs a rebuild. I am in SOCAL so if anyone has a shop that can do it at a good price let me know. But anyways I haven’t got into the car to diagnose myself but let me know what to look for . It’s a 4.0, I’m hoping that it holds compression it is there any problems to look for? And does anyone know a price on a top end rebuild and a full rebuild? I’m young so I don’t got much so if it isn’t worth it I won’t do it

 

Welcome.