The best way to evaluate the quality of the work is by checking with their past clients. Once you get a hold of their portfolio, you will have many client testimonials to check. Another way is to check out their website and to check out google reviews. However, it is not very often that a freelancer would have their website. But it would not hurt you to check. Ask them if they can give you any of the clients’ contact numbers to call up or message to know about their service. A good, genuine individual would not have any problem with that.