'You can find hotels at a price
of about (or around) 50€.' would be correct.
And to make it clear that it's not the
hotel that will cost 50€, but a
room at the hotel, it would be better to say 'You can find hotels at a price
of about (or around) 50€
a night'
But best of all would be simply 'You can find hotels at about (or around) 50€ a night.'