Hey there,
I understand that you're looking to make some changes on your existing website. Also, I have taken note that you need to upgrade your Opencart version and set up default filter. Well, I am delighted to inform you that I can work on this project and make it a success for you, as I've multiple years of experience with Opencart.
I have excellent work history, top ratings & feedback from my clients, so I assure you that you're in the right hands. If you have any questions or concerns, please let me know at earliest.
Warm wishes,
Wasif