also 140k on 17-19k mate and you wont be able to leave the house to enjoy yourself.

i was 20 when I bought my first house for 43k - just bought one for 140k now - with a 90k mortgage - im on a fair bit more than 17-19k - but after all my regular bills I wouldnt say I had much cash spare!

140k - will be at least 700 per month payments... council tax bank on min £80 a month... insurances another £40... gas elec £50 a month - water bill £20...
food £150 a month - petrol £100 min - car insurance £30 a month?

I'd say you were out of money already per month... and you've not bought TVs, decorated, replaced any fittings, furniture or had a few nights out on the pi55....

You could do with a rethink mate.
for a guide £1000 mortgage will be around £5-7 per month payment.
the other bills are all around the same regardless of house size