My guitar is missing a string. I was wondering how much does it cost to get it fixed plus the sting cost.

If it's a normal guitar, (not a nylon string, or equipped with a Floyd Rose type trem system) a full restring is $20, plus the strings. The strings run anywhere from $5- about $15 a pack, depending on your preference. If you really only want/need one string replaced, you can get the string for about $1, and someone will probably just throw it on for you. If your strings are more than a few months old, I'd recommend a full restring. The tech will usually clean up the fretboard, polish the guitar, etc. Hope this helps!

It depends