large car low costs - wazza
here is one for u

looking for a mondeo or a larger car. low insurance and parts are high on my list. since i only use the car now and then for short journeys mpg is not important

budget is 4k max
large car low costs - Screwloose
wazza

How about an old Ford Scorpio 2-litre? Or even a 3.9 Range-Rover? Specialist insurers and cheap S/H parts everywhere for those. Doesn't fit your given conditions; but for 4K, a Previa would be my choice for lots of space. Occasional/short run use can be problematic for many cars: they like to be used moderately and often.

If you're doing less than c.3000 miles a year; then a broker-recognized classic car can be peanuts to insure on an mileage-limited agreed-value policy. Old Rover/Jag/7-series/Merc or similar?
large car low costs - Buster Cambelt
The Old GM Omega was always a decent old barge and pretty well built too.

You can get nice old shape A6s pretty cheaply too and they simply don't break - as long as you get them serviced properly.
large car low costs - Garethj
Ford Mondeo? The recent ones are bigger than a Scorpio!

Volvo S80?

Mitsubishi Galant V6?

Nissan QX?

The Audi A6 can be a bit pricey to repair (as can most cars in this sector to be honest) so perhaps an important factor is a friendly independant garage.
large car low costs - Buster Cambelt
But A6s don't break, apart from a battery and tyres I have replaced only the side repeater lens in 7 years and that cost 5 quid
large car low costs - MichaelR
Have to say Mondeo.

Loads of kit, very reliable, cheap to fix and great for short journeys.
large car low costs - Garethj
But A6s don't break, apart from a battery and tyres I have replaced only the side repeater lens in 7 years and that cost 5 quid

One swallow doesn't make a summer, my friend's A6 last service came up with £2000 worth of faults. Quite a lot for £3000 worth of car.

Hence my point about finding a friendly garage who can help you sort through the vital repairs against the 'nice to have' ones