When should i call?

Today i was playing a heads up match with my friend for £25, winner gets £50.
We played for about 20 mins and he decided he couldnt be bothered to play and he was going allin every hand.
So he stole my blinds for 4 or 5 hands and then i decided to call him with K10... he had 85 and hit a straight on the river. I was fuming at this point.
So my question is, what hand should i go allin with against someone who is going allin every hand??????

any PP or A10 and above?..., really that's a tough question but standard rules apply.....patience until you get a playable hand. Until the blinds get so big that you are forced to move, let him have your 20/30/50 bucks.......when you get a good hand wait for the push and get it all back.