error codes and advice 98 LSC

[DreDaDevil]

hey guys, i need some help with a 98 lsc. she's giving the following codes. p0306 p0307, which if i am correct are misfires. also codes p0171 and p0174 as well as p1131 and 1151. should i just give up on this car or go ahead and spend the money? btw, on average, how much will i have to spend?

 

[slowmkviii]

Sounds like it need a good tune up.
And price depends on how much work you do.
So plugs, possible coil packs and valve cover gaskets,and o2 sensors