I also wanted to point out that you should avoid buying HitReg Fix plugins for CS:GO if you don't know exactly how they work. A popular fix made by backwards that is ran on many Surf Combat and AWP Bhop servers includes models with large hitboxes and do not fix hit registration in any way.
Please remove these plugins/models from your server.
https://i.imgur.com/zsjc565.png
If you believe your server will have better hit registration with these models then take a look here:
https://streamable.com/xx9qpu https://streamable.com/tr0ufc (NoSpread 100% Accuracy Enabled with hitboxes shown above)
Please feel free to correct me if any of my information is incorrect
All of the fixes above have been implemented into a sourcemod plugin + another fix for
WantsLagCompensationOnEntity. Latest DHooks + Detours is required to run this plugin. (Thanks to D34DSpy for helping!)
https://github.com/br69ks/Hit-Registration-Fix
This fix will remove network compression from all variables as described in the first post:
https://github.com/br69ks/Netvar-Compression-Remover
You should also include these fixes on your server as they can both improve hit registration and other issues related to Surf Combat:
https://forums.alliedmods.net/showthread.php?t=315405
https://github.com/GAMMACASE/PushFixDE