Finding the right premises

Hi all.
I am looking into starting a hostel in Lithuania, but by far the biggest obstacle is actualy finding the right premises.
A friend of mine already rented a flat in Lithuania and made it into a 23 bed hostel. The place was originally advertised as an unfurnished apartment for residential purposes, but my friend somehow made a deal with the owner to use it, legally, as a commerical premises which is now a fully licensed, successful business.
How is the best way to approach estate agents and owners when looking for a flat to rent? Obviously, virtually all owners will say no way, but looking at commercial properties for rent has also yielded no results, since they are all office or retial use whereas, of course, a hostel is best suited to a residential apartment, none of which I have ever been able to find where the owner will agree to rent out for this purpose. Anyway, any tips would be appreciated. What is the best way to approach an estate agent / property owner when looking for a flat in which to establish a hostel / guest house?