What is a good response to say when a person not of the faith states that Catholics 'earn' their way into heaven by reconciliation and doing other things while non-Catholics accept Christ and are welcomed into heaven because of this'?

First of all the Catholic Church has never taught that one can "earn" their way into heaven, that, somehow, we can be justified by faith and works. When a person comes to know God through faith, he or she is initially justified and does not have to do a certain amount of good works to enter into heaven. However salvation can be lost through mortal sin, which requires full knowledge and consent.  If one commits mortal sin, he or she must repent and go to confession. If one does this, he or she can be restored to justification. No amount of good works can substitute for taking mortal sin away and regaining justification. That said, good works do have a role in Christian life. Ephesians 2:10 states that we are "created in Christ Jesus for good works, which God prepared beforehand, that we should walk in them." The letter to the Romans also state that good works flow from the love pours in to our hearts (5:5) at our first justification and that God will ultimately reward those good works (2:6-7). Furthermore St. Paul not only warned his Christian Corinthian audience of certain actions that could cost them the kingdom of God (1 Cor. 6:9-10), he also told the Christian Philippians that they must "work out their own salvation in fear and trembling" (Phil. 2:12). That doesn't sound like a man who feels he has salvation locked up by merely accepting Christ.