Thanks for the advice and information. When we got to see the bike it was in very good condition, in my opinion anyway, but when my friend tried to sit on the bike she found out that she could only just get the balls of her feet onto the floor.
After asking at the Yamaha dealership about lowering it they said that, from what they could find out, it could only be lowered by about 25mm (about an inch) so that wouldn't make enough of a difference so she's decided not to get an MT
Find her a bmw f650gs... that is perfect for female and short riders.
Because they are looking for a 2nd hand cheap bike that wouldn't cost more than 2.000 pounds..Why not try an MT07. I thought the seat height was quite low on that and it's a very light bike as well.