Anyone here good with Renaults?

I have bought a 2013 grand scenic mk3 (first mistake)
Today the sat nav says no gps signal which was working fine yesterday.

And radio is being a dick,
from day one there has been no sound from the left rear speaker.
Only around 20% from right rear and front right speakers.
The front left is fine but overall the sound is awful due to the other speakers.

So I have reset both the radio and sat nav no difference.
Updated sat nav through TomTom with no difference.

I don’t know what to do now?
I don’t want to buy a new head unit as they are £200 second hand and I can’t fit aftermarket as it’s built into the dash.

Today I have ordered a new radio head unit £65
and a gps antenna off eBay for £5

im hoping to solve the issues above the cheap way.
I have also purchased a centre console with armrest as my car only has a shit cup holder tray thing on the floor.

now my next issues are aircon is bollocks
And every now and then it won’t accelerate it just seems like it’s in limp mode and then it will go.