Phonecalls I'd still log times and if you can, the content. If it gets messy you really want to note the timings and how the conversations went. It's good that you mentioned the £500 in the email as you have a record of it now.
They then can't deny it later (of course they could just not reply to the email). If they don't reply to the email and call you instead then be sure quote/reference key bits from the phone call in a follow up email.
I think the £500 comes from there being something about deducting money for wear and tear upon return but I really don't think that applies here given the timescales.
Btw I thought the car was small fry in my case as well, but it doesn't matter to these scumbags.
Will do that too - thanks for all the suggestions, specifically the help you've provided in this post
@sigma and to all the other people chiming in, I thought I was on my own and would have to just duke it out with the dealer (still possible of course), but knowing I'm not being unreasonable has helped, so cheers.
I think of the 100 cars they've got for sale mine was, value wise, in the bottom 5%. I appreciate their mark up on it might be higher, don't suppose we'll ever know what they offered the last owner.
Oh, and speaking of the last owner, the dealership told me yesterday that "the previous owner was a lovely chap who fixed everything on the car, he'd have told us if there were anything wrong with it"

- like, how dense are you, or how dense do you think I am?
If he was able to jump start the car then it's definitely something to do with the battery not being charged, or something draining it.
The washer jet one is a weird one, maybe (surely??) they did attempt to fix it for the MOT, did the motor/pump make a sound when pulling the stalk?
Yeah agreed, 100% something wrong with the electrical system at some point.
Pump still engaged when pulling the stalk, probably just the jets clogged (this wasn't a massive issue for me, I'd resigned myself to fixing that, as I know it would have niggles), honestly my main criticism is that it's failed to start on me twice, the other bits are certainly annoying but I was willing to spend money on getting them fixed, but taken as a collective, I just have no trust in this car anymore. And in a couple of weeks, I'll be out of the timeframe to reject it.
And actually leaving the new battery in there is good grounds for you saying you accept it's an old car and will have some wear and tear, hence you did spend money on it. Definitely remember this bit in case it does go down the small claims.
Good shout - yeah I think I've been reasonable. I don't know how ugly it will get but clearly I wasn't trying to run it in a shoestring, less than two weeks into ownership I'd already put a new battery and two tanks of premium diesel in it, with a further couple of grand planned to sort out tyres, brakes, and the washer jets.
I have two other cars of a similar age, one an E92 from 2006, had it over 3.5 years so I know these things aren't plain sailing (appreciate an E70 is not an E92).