Car making slight squeal when accelerating

[Delgirl]

I posted the other day to say I was thinking of selling my Audi A3 DSG, my mind may have been made up for me!

My husband took it today and gave it a good run which it hasn't had for a while. This evening he noticed when he set off on a journey it was making a slight squealing sound when accelerating, it's not very loud but you can get it when in car or stood nearby. I just took it out and it seems to come on when first accelerating so only for a couple of seconds at a time. Could this be the fan belt and if so is it an expensive fix?
On top of that he noticed a couple of drops of oil on the drive when I took it out, this is new too.
Please advise on potential problems and cost implications... the car has had no problems whatsoever but is 11.5 years old and I've had it from new.
Thank you in advance

[Delgirl]

Thanks guys much appreciated. I took it to my mechanic and he found no problems.
With me selling it and a friend being interested, I didn't want to sell it with problems so he came to have a look and listened and he agreed it was the belt and is happy to go ahead with the sale.
Phew!