Can I do the upgrade/migrate on my own?

I am about to move my site from 2.3.0.2 to 3.0.3.8. My live site is very stable on 2.3, but I don't want to be at back as time goes by so I decided to move to 3.0. I am planning to make a clean install of 3.0 in a testing environment first and then copy necessary custom files and folders such as images and database tables from 2.3 to 3.0. I know some db tables can have different structures, so I can't simply export and import in between. What would you suggest when copying db to the new one?

Although I am a semi programmer (not experienced at all), I have some quite a few knowledge about Opencart. I would like to ask what you experienced guys would suggest to me in this project. Can I do it on my own? What are the things to be important to care of?

Thank you!

Sounds like you can do the upgrade but prepare for any problems along the way. Backup, backup and backup again. Files and database. Then you can easily roll back if the upgrade is problematic. I suggest cloning your live site and try the upgrade on that before doing it for real. Personally I would say if your live site is working well and making you money I would leave it on 2.3.0.3. You could consider upgrading to one of the alternative 2.3.0.2 versions such as Condor's excellent version. I wouldn't see a busting need to upgrade to V3. All in my humble opinion.

You can use our free Export/Import tool to copy attributes, options, categories, and products from OC 2.3.0.x to OC 3.0.3.8, see our FAQ on how to do it.