Blender is a powerful program and if you don't have a fast enough rig, you won't be able to do the things you really want to. Forget about simulations, or large scenes.
Get 32gigs of ram or more, (ddr5 ram just dropped in price), Get a VideoCard with 12gb of vram or more, get a large M.2 drive, and an 8 to 16core Processor.
Here is another @leledoesdoodles DTIY challenge from Instagram, I really like her style and I tried to push this one even further.
I sculpted the character mesh in ZBrush reusing some old meshes, then retopo and tweaked everything in Maya. For the clothes I used marvelous designer, ZRemesher and Maya. (I built a small tool to transfer the retopology and UVs in Maya). The character was rigged in Maya and tweaked after posing. Textures were done in Substance Painter and rendered in Arnold. Hair was done with XGen.
I hope you like it,