take a look here https://www.ebay.co.uk/itm/175416792200

i would clear all the codes and check again in a wk or so and see if any re-appear, as you don`t know how old all them codes are

so if new batt is not getting the car started still then yes starter motor next, any good garage should be able to check that for you, did you fit the correct batt for your car

I always use a small independant local garage. To get your batt checked use kwick fit. Halfords etc. Once you know if the car batt is no good order it online and fit yourself £110

Tryca good brand of 2032 batt for the keyfob. They should last around a yr

Take a few mins normally with engine running

Any good garage should be able to test the condition without telling you that you need to replace this and that

Looks like the led screen is on the way out. Think you would have to replace the whole unit.

I got my local garage to do my belt etc 2yrs ago just over 4hr job . £420. I could have supplied all the parts myself and would have been even cheaper

Think you will find its not that easy just to swap over as wires will be diffrent as i think your current unit installed won't have camera views etc. Yes you would need to add gps and you would need to get your new unit unlocked to your car aswell as its not gonna be plug and play.