Hotel Reservation is needed to let you in to hongkong ?

I'm planning to go to hongkong for a week in august but i dont want to book a room in a hotel in advance .. SO will they let me in without a hotel reservation no invitation and then i can find the place i want upon arrival Or they should check the hotel reservation to let me in ??? FYI i have taken the chinese visa and went there 2 years ago ..
Thank you
Best regards