I try to model a high-poly T-rex, but the upper legs are always a little too bulky no matter how good I try. Are there any good addons that I can use to assist in modelling, rounding out parts of the model that are too bulky, and for fixing up parts of the mesh that show through? Modelling can be a pain sometimes, especially with dinosaurs like the T-rex.
Can anyone point me to somewhere that has any good free addons like these? Thanks in advance.
Well… this emphasizes the importance of proper proportions in the low poly phase 
… and you can even use the smooth brush for low poly…
I like the contour tool of retopo flow. As for assistant modeling, you can use sculpting tab. I find the sculpting tab of blender a giant cheat because you hop into it while youre modeling and you give brush strokes so you dont even have to move vertices manually
Whats contour tool and retopo flow?
You may wanna look here :
(…and may also not tag an answer a solution if you still have some questions… )
its an addon for retopology and one of the most expensive ones, so before purchasing it I would advise you to at least try it and downloading their free addon from github…
People really promote this addon, but I found it useful only for the contour tool, which allows you to distribute equally a circular array of vertices around a section of the mesh you want to retopologize. The rest of the tools it offers are unintuitive according to me… BUt its nice to have this addon because blender is in competition with other softwares so it has to do everything… this addon closes a gap and even if you dont like it its still good that its there.
I’d probably not, I don’t like paid addons, sorry.
Draw X-ray is very useful when making ears
Check out 167 pages worth of BNs addon section, should be something in there too tickle your fancy: