Audi A6 and BMW 5 Series too fancy ?

[Sysman]

How else can I possibly know how many hours, minutes and seconds to invoice for if I don't?

I've worked at a few places with a timecard system. Some were better than others, the best one of the lot telling you how many hours and minutes you'd done in a month. Easy peasy for invoicing purposes and proof that you had actually been there.

[Sysman]

Maybe get a lovely car, but a couple of years old so it doesn't look all shiny.

That's been the strategy I've had most success with. You let someone else take the initial large hit of depreciation, and a second hand model that's loaded up with extras costs little more than the bog standard model. In fact go for the bigger engined model and it may cost less up front. Definitely worth it if you plan on doing lots of commuting in my opinion.

When you do sell it, compare what you get for it with what the car you could have got brand new for the same outlay would have fetched, and smile.

Then park near management so it doesn't stick out.

But not so close that they spot the Quattro badge carefully concealed in the interior only

[Scary]

Funny how people have no idea what a car's worth, you can buy an A6 for 1500 quid, put it on a private plate and give it a polish and you'll get quips about how you're paid too much, from people who spent ten times that on a new Mondeo.