Best bang for the buck?

You don't think after having the combo for 7 years he may have tried a few things like a tune-up..

Well, I have no idea what he has tried so far, and it is his money.
He stated he had limited funds. I have found over the years that people who are disappointed in their cars performance are still disappointed after dumping a lot of parts,[money], into it , if......they don't learn to tune.