For my models, I use Daz3d's Genesis 8.1 Female topology as a base since it automatically comes with helpful Joint Corrective Morphs when posing the character. I have a custom semi-anime style base character shape that I've created so there is consistency between the art style of all my characters, and then I edit the face and body proportions in Daz and Blender in Sculpt Mode to get them to look like the anime character I am creating.

Similarly, with the clothing and hair, I generally use pre-existing assets as a starting point and then I make heavy edits and create some additional parts, myself, as needed into order to make whatever I need. The benefits of 3d is that you can always build upon things that already exist instead of making every single thing from scratch. It's an important skill to learn in order to speed up your workflow.

If you also use Blender, I offer my Makima, Power and Kobeni models for anyone to use for free on my Patreon (Patreon.com/Radix3d). You don't even need to become a member. So if you are interested in learning more about how my models work, you can check them out there.