All I know is that the secret hut is in area 3 in Fuschia city in the Safari zone.
after catching latias/latios YOU DO NOT HAVE TO CATCH LATIAS/LATIOS TO MAKE A HUT!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
it's in the scret hut in the safari zone in Fushia
With the secret key which is found in the Pokemon mansion.
you must be getting it messed up with Pokemon ruby version. there is no secret slab in Pokemon mystery dungeon. at least in red or blue.
At the secret house of Safari Zone.
just wast money on gameshark and get the code
You have to beat Giovanni in the Secret Basement beneath the Rocket Game Corner.
It is just a different color of the red tent, which is a secret base item that hides you.
You need to acquire the Secret Key that can be found in the basement of the Pokémon Mansion and then you can use the Secret Key to enter into Blaine's Gym.
in the hut
The secret Pokemon house is in the safari zone in fuchsia city. I used a very useful website to get to the secret house inside of the safari zone and it told me where I had to go. Use the link at the bottom and it'll tell you exactly where to go inside the safari zone to get to the secret Pokemon House. Once you are in the secret Pokemon house you will see a guy. talk to him and he'll give you the HM03 (Surf).
Basta! Secret Na Lang Yon