Confusing sentence

Confusing sentence
 

Hi people. I can't make head nor tail of this sentence. Its abundance of articles, pronouns and prepositions are overloading my poor brain.

"Si a estas se les unen las más de sesenta de las que ya se disponía de los propietarios privados, ..."

More context is needed here, but roughly this means:
If at these (chambers?) more than seventy of those in charge of the private owners met.:thinking:

I will add an object (apple) to make it easier to understand.

"(...manzanas.) Si a estas (manzanas) se les unen las más de sesenta (manzanas) de las que ya se disponía de los propietarios privados,..."

"(...apples.) If these (apples) are joined by the more than sixty (apples) (that were) already available from the private owners,..."

NOTE: I'm not sure about that translation, spanish to english isn't my specialty xD


"... las más de sesenta (manzanas) de las que ya se disponían..."

de las (manzanas) = of the (apples)
que ya se = already / (that were) already

de las (manzanas) que ya se = (of the apples that were) already
disponían = available

I agree the whole sentence is needed and the context, however it may be something like:

"If these are added to those from private owners, of which more than 60 had already been taken/disposed of..."


Edit: Cuholvke beat me to reply, but maybe some other proposal will help anyway. ;)

Only the meaning, no matter the context and the sense of it:

If you add these thingies ("éstas") and the set of >60 (thingies, presumably) among those privately owned (or "from private owners") which were already available...

(those "more than sixty" should have been named before in the text as a subset of all the thingies available from private owners)

Thanks everybody, the meaning is clear now. By the way, the object was habitaciones.