Instead of hiring a freelance / contract base developer, I suggest you to contact to a professional company that have team of professional, committed, work for pride and want to build healthy relationship with you in future. Better to hire those who near to you or at least you can visit them. Set terms and condition and sign a contract with them.
If you still feel problem to find the good one, contact to me. Hopefully try to settle your query and give you peace of mind so you can concentrate on your other business areas.