Shed advice - Renault 1.5d ? VW 1.4d? Reliable engines

[Engelberger]

So I have a few classic cars that I use depending my mood.

I want a shed with the following criteria:

Reliable
No big tax bill
High MPG
Easy and cheap to maintain

This will be used as a mile muncher across the UK, mainly on motorways a couple of days a week. It will need to carry a couple of overnight suitcases and a bunch of kit like tools, wet weather gear and other bits and pieces.

I am wondering what engine is the best to go for. 1.5d renault/nissan engine? 1.9tdi VW? Audi 1.4d?

Want to spend less than £1K and it will be totally misused unlike my other cars.

Ta

[Silenoz]

Anything with the VAG 1.9 TDi lump in, can't go far wrong with that.

[BlueMeganeII]

The 1.5 dci has never been reliable, ever, in any of its iterations.