Hiring coder for first time: Things I should look for?

I'm looking to hire a coder for first time for a small project on oDesk. Normally with PHP I usually code things myself, but in this case it's a bit complicated and I don't have the time.

Is there any particular things I should ask or look out for?

The job in question is to code a payment module for a shopping cart(ZenCart) to connect with PayDollar(an Asian cc processor).

 

Remember to backup your website site files before giving access to your server. Check for credentials and past work experience. Change your passwords and then change then back once work is complete.

 

Check for the coder's work experience, portfolios.

 

You are savvy enough to ask for advice, unfortunately a significant number of employers place too much trust in would-be "developers" that unfortunately don't deliver and more often then not, cause more harm then good. I've been in similar circumstances myself so before hiring any contractors, I now do the following;

Feedback - oDesk and similar platforms such as eLance & Freelancer.com allow you to check contractor feedback. Whilst reviewing feedback, and if possible, take a look at the folks that have apparently left the feedback. Many contractors create fake accounts or pay users to leave positive reviews.

Google history - Run their name/username or if possible their Email through Google. You'll be surprised how much history you can uncover and has certainly assisted me in the past.

Portfolio - Always request a portfolio!

Security - As another user has rightly mentioned, back-up your files and ensure the passwords you are using to access web hosting or FTP related services are UNIQUE. Be sure to change them once any work is complete.

Kind regards