I’ve been on ROBLOX since 2014 on a different account and have been doing UI Design for 1.5 - 2 years and I thoroughly enjoy it.
You can also view some of the UIs that I have open-sourced here
Almost all the UIs that I create are made 100% in ROBLOX without and other 3rd party programs like photoshop. Some of the examples above use stock icons as placeholders, I am not claiming to have created these icons.
UIs start at R$2,000 or $10 USD and will increase based on the work requested.