"The house has some simple rules."
Translation:La domo havas kelkajn simplajn regulojn.
The word "facila" means "facile" or "easy". So depending on the context it can be interchangeable with "simpla". But, as in English, they are often used to mean different things. My dictionaries are packed, so I have to rely on on-line sources at the moment. But here are the two words contrasted on http://reta-vortaro.de
"Facile" is defined as either 1) Senpene farebla (effortlessly doable) or 2) Senpene eltenebla, ne peza, apenaŭ sentebla, neintensa (effortlessly tolerable, not heavy, barely palpable, not intense)
The first definition for "Simpla" is very similar: 1) Nekomplikita, facile komprenebla, uzebla, solvebla (Uncomplicated, easily understandable, useable, solvable) . But it's additional meanings are quite different: 2) =nura (mere), 3) Simplanima, senartifika, senruza, eventuale naiva (having a straightforward soul, without artificiality, without cunning, naive).
I know this is an old, but for future learners:
iu = some [thing], someone io = something
We never put a noun after io, it is a noun in itself. Iu works like an adjective that goes before the noun (if it's by itself you're talking about a person, "someone").
La domo havas iojn = The house has some things. [an unspecified amount of unspecified things] La domo havas iujn simplajn regulojn = The house has some simple rules. [an unspecified amount of specified things]