Leasing and MOTs

Hi - I currently have a 3 year lease on a Range Rover Sport and I'm thinking of extending it to 4 years rather than putting down a big deposit on another lease.

Now I know there is much debate about leasing vs buying but that's not what Im concerned about here. My main concern is if I extend then Im outside warranty and will also have to MOT the car before it goes back to the lease company.

I know every car in the world is different and its a bit of a 'how long is a piece of string' question - but...should I expect to have problems with an MOT after 4 years, is it usually a formality or are there things that usually start breaking/need replacing at this time (I will have serviced the car according to schedules).

Thanks

Firstly I would check it over and see if there are problems that are likely yo cause a fail. Can you get it serviced under the current contract so there are "no surprises"?
Then what could it fail on? Mostly modern vehicles will not fail at 3 years on anything corrosion related, if its been driven hard you may get suspension bushes, but these are not huge costs.
The things you want to avoid are emissions fail because this could by any number of things and involve a lot of work, also any active systems, ride hight, ABS, traction, that could show on the dash and give a fail. These too could get very costly.
You could take it to a local MOT place and pay for an emission's check, probably £20 or so. If its passes there's a good chance it will pass the MOT, you could pay for a "pre-MOT" - can't be more that £40. this would give you some hard facts to base your decision on.
This deals with the MOT, but not breakdown costs. As these can come without warning and cost a packet I would take out an extended warranty for the 4th year. Lets take worst case; there are a number of people who have posted on here who have had cranks break on TDV6s, this is a £10k fix so its worth (say) £250 to get extended cover.
My personal view on high end complex vehicles such as Range Rovers is that unless you can afford to write it off and not notice you should never buy one, drive it by all means but make sure it belongs to someone else; either as a lease or company car. The potential repair bills are just too high for anyone on a "normal" income.
You are in transition from the safe (and sensible) place of driving but not being liable, to being liable, so I would put in place a few sensible precautions - get it serviced, get it checked, get warranty cover.
There could be a step down in vehicle value over the 4th year as its is now "old" to some people and its in that difficult place of too old for wealthy buyers and too expensive for Joe average. Who picks up this fall in resale value? Could be a decider.

What mileage is it on?

You will need to mot it twice, once at 3 years and once at four when you hand it back. You know the vehicle best, you also know whats in the mot(if you don't its publicly availible) so you are best placed to say if it is gonna pass or fail. Is anything broken, worn out or run out?

Should generally be sundries at most at 3yrs.