daily commute is a 100mile round trip ...

currently running a 1L Ecoboost Fiesta which is costing me around £80-£100 a week on fuel depending on what other journeys happen during the week.

With the info above your are you saying on a week where you do no other mileage than your commute you use £80 of fuel? If that is the case your Fiesta is only averaging 34 mpg whereas HJ's real MPG suggests 44 mpg is what people are actually achieving but in truth i would expect you to get more than that with your long runs, our 1.0 Fabia with similar power but a mixed use does 50 mpg.

The suggestion above of the 1.8 petrol Avensis will actually cost you more, based on HJ's figures about 10% so if you are wanting to save forget that one.

But the best way to save money on fuel is simply to drive slower. Your trip to work of 50 miles at 70 mph will take 43 minutes, drop your speed to 60 mph and it will take 50 minutes and since not all your commute will be on motorways the time difference will be less. When they were doing roadworks on the wifes commute and had a 50 or 60 mph limit for about 2 years her mpg in a Focus 1.6 TDCi increased from about 48 mpg to about 53 mpg,quite a saving.

And don't forget that changing cars to purely save money never works. What you save on fuel is spent on repayments several times over and unless its a new car you buy there is a good chance of buying a money pit.

I have an Avensis estate, petrol and auto. I visited an elderly relative yesterday that involved a 214 mile round trip on almost exclusively fast A roads and motorway. With less traffic on the road there is much less stop/start and driving at a steady speed is easier. I was doing a steady 65/70 and not pressing on, yet still managed to do the journey in very near or record time. Anything less than two hours is really good going, and achieved in both directions. I filled up before leaving and then on return and brim to brim using the same garage (Sainsburys) gave me 46.31 mpg. I can touch 44ish on a good run and would be disappointed with less than 42 for this trip, but this is a record high for me and that was without trying.

The car has now done 45k and in the two and half years I have owned it I have done 34k of those. I paid £14k for it and reckon I could easily get 11.5 or even 12k for it (good nick, spec and FTSH). Just brakes, tyres and routine service and no other problems.

A really great car and no turbo, DSG box etc to worry about. Everything works, cheap to service and coming up next February to five years old. A Toyota two year extended warranty is £495 and includes european breakdown cover, two MOTs and an MOT guarantee. Whats not to like? They sell like hot cakes apparently. If you can find one, buy it!

>>From the 2015 facelift, before that it's a Toyota AD series.

His budget was £15k or thereabouts - 2016/2017 moels cost around that figure = BMW 2 litre.