Web Site Development -- Potentially Ongoing

I need a designer who can get my site back to being fully functional. The plug-ins are conflicting with each other and whenever an order is placed, I get an error. There are two projects I need completed right now. I will possibly have more to come.

1) Troubleshoot the site and resolve current design issues.
2) Troubleshoot payment system and determine why an error is created at checkout.

https://www.ezstreetnumbers.com