Do yourself a favour and do not ask anyone for directions. There are 2 large buildings near the McDonalds. Go to the one further away. It is a 9.5 story building and the hostel is entered by the shops on the ground floor. It is a nice modern, very clean hostel about a 10 minute bus ride from the centre. There are 12 rooms accommodating from 1 to 5 and costing from 90Hr to 350Hr per night. There is no kitchen or communal room but there is a TV in every room. The staff is friendly and communicates well. They will be happy to help you plan your excursions and sightseeing while in Lviv.