First of all, NO AGENCIES. Only individuals.
Please answer the following questions:
1: Which programming languages are you the most skilled/experienced at? (front end or back-end)
2: Which project are you the most proud of? Can you show me examples of your previous work if I ask?
3: How much time per week are you available for work?
4: Are you a full time freelancer?
5: How many years of experience do you have?