all GP's and SP's not working

I've had this problem for a while and it's still not fixed. I've been through all my mods and updated everything I can. It's just not working at all.

Could it be that you installed the latest fix 1.30.105.1020 or 1.31.36.1020 that are intended for the base game only.
These fixes remove all DLC's from your game.

Hey no i did not install either of these. I was aware they are for people who want the base game only. 

It works sometimes and then doesn't.

Everytime I add new CC it seems to just not want to work. Even when I remove that new CC it might work but then sometimes I'll remove any other random CC that has nothing to do with the new one and it will work, so I know it's not the new CC that has broken the game. 

For example, I downloaded a mod and tried to run my game, and sometimes it wouldn't even start up but when it did, it said Game data incomplete. So I exited and removed that mod, and the game would still not work so I'll delete another random CC and it might work. I'll put the mod back in and it sometimes works and sometimes doesn't.

It's a really inconsistent problem! I love CC and I don't have loads of it, I recently cleared it out because of these problems but everytime I put something new in my game has a meltdown!! I have nothing in my tray, no lots, its mainly clothes, hair and furniture/decor.

First of all rename your folder The Sims 4 in User\Documents\Electronic Arts to The Sims 4_old.
Start your game - you'll have a completely new game now.
See if the problems still persists.
If not then your CC causes it.
If yes, you can delete the newly formed folder The Sims 4 and rename The Sims 4_old back to The Sims 4.