Here are the locations of all of the flyers distributed by the Wutai bar Turtle's Paradise.
Once you've read all 6, talk to the guy behind the bar in Turtle's Paradise. He will give you one of each type of source, and a Megalixir.
N.B. The Shinra Mayor's password is randomly generated each time and changes from game to game. So there is no simple 'this is the password' solution. But some help from my guide should see you through.
You come across the Shinra Mayor on Floor 62 of the Shinra HQ on Disc 1. If you get his password right first try, he will give you an Elemental materia as well as his keycard.
To work out his password, visit the 4 libraries on this floor. The sign outside each room tells you what the topic of the room is. View the various books in the library and see which one doesn't belong in each room according to the topic of the room. After each book is a number. This number corresponds to a letter in the book's title. So if the number is 9 for example, you want the 9th letter. Once you have all 4 letters worked out unscramble them for the password.
To open the safe in the Shinra Mansion in Nibelheim you must go through the numbers in either left or right direction before selecting. You cannot go past the numbers so be careful! You must land exactly on each number in the correct direction without going past the number.
The numbers and directions are:
Upon successfully opening the safe, you will face a boss, Lost Number. Defeating him will earn you the item for Red XIII's level 4 limit break, Cosmo Memory. You can then pick up the Odin summon materia as well as the Key Item 'Basement Key', which will allow you to get Vincent Valentine to join your party from the Shinra Mansion basement.
The code to get the Huge Materia in Rocket Town in Disc 2 is: Circle, Square, Cross, Cross. On the PC, it's OK, Switch, Cancel, Cancel (Enter, Delete, Insert, Insert with default controls).
I can now confirm the code on iOS (iPad, iPhone, iPod touch) and Android is: A, X, B, B. Note that this doesn't match with other versions, as Cross on the PlayStation version would correspond to A on the mobile version, meaning it would have ended in A, A; not B, B. They went and switched things up to trick people... :)
Want to enter the FF7 property market? Well if you like, you can buy the villa in Costa Del Sol for 300,000 Gil. Of course there are a good few locations around the world where you can sleep for free, but there's nothing like owning your own villa rather than bumming it. Also, the villa is set in the luxurious, sunny, beachy setting of Costa Del Sol, a prime location...
In order to purchase the villa, head downstairs and talk to the dude in the basement.
The W-Item cheat is an easy way of building up unlimited quantities of certain items in Final Fantasy VII. The impression I get is that it's actually not a deliberate cheat built into the game, but more of a bug.
First of all you need to know where to find the W-Item materia. In the return to Midgar at the end of Disc 2, when you're in the Subway, head down and keep going along the train tracks. When your team tell you you're going the wrong way, just ignore them. Eventually you'll reach the end with a save point and the materia.
Simply equip the W-Item materia and get into a battle. In the battle, select an item using W-Item and go ahead as if you're using it. Then select the second item, but this time don't use it - just select it and then press back (circle then cross on a PlayStation controller). You will see you now have one extra of this item. Keep pressing select then back to build up as many of the item as you like, up to the total of 99.
This tip is particularly useful for building up Megalixirs and Hero Drinks before fighting Emerald or Ruby Weapon, or Elixirs when fighting Magic Pots.
Limit Breaks Guide
Enemy Skill Guide
Final Fantasy VII Remake Guide
List of Every FF7 Title
Other FF7 Websites