Seriously ? , you're considering buying a car that's been off the road for five years without an MOT ? , as Don said , this is a long time for a car like this to be idle and could throw up all kinds of problems , and that's why he hasn't offered the car with an MOT .
Make no mistake , the tester will have it up on a ramp and look at things you never imagined , unless this car is something special such as very low mileage or is in exceptional condition why burden yourself with an MOT on an unknown car which you will have to do immediately ?
Have you got a link to the car ? , i've looked and cannot find it , maybe if we could see it , find out a bit more about it we might agree it's worth the money and worth taking a chance but , it's never a good idea to buy the first one you see as you have no yardstick to judge whether it's good value for money , there's cars out there in good condition with an MOT for that kind of money which at least gives you time to get to know the car before the trauma of the MOT .
Personally i would want to look at a few more before purchasing , it's a buyers market and cars without an MOT go cheap [ for good reason ]
'93 4.0L Daimler, solent blue,
'93 4.0L Daimler, Westminster,
'85 2600 Rover sd1 vdp oporto.