One free company owns 13 houses in one Empyreum ward on my server.

[Garten]

Obtaining a company petition in Ul'dah, Limsa Lominsa, or Gridania.
Filling out the petition with the company's name and tag.
Get three signatures from three other player characters in the same server. (Level doesnt matter).
Return the petition and pay a 15,000 gil registration fee. Et Voila.
Wait 30 days.

What a shocking exploit. OMFG. The Worlds End is near.

you explained creating a guild, not obtaining a house with that guild (that you should not be able to do it if you have already one, like i explained a few posts above)