What does 。。んだようなものだもんね mean in this sentence?

Question

I have problems translating the last part of this sentence, specifically the part of んだようなものだもんね

寮が個室だからこの学園選んだようなものだもんねっ

Let’s go by parts as Jack the Ripper said. Haa! Haaa! I know that the ん means a way to emphasize a phrase, that だ is a casual form of で す

And it gets more complicated with the next word よう(this word scares me when I see it, really), using as reference the online dictionary Jisho.org we have several possible translations

ような＝様な

よう＝用

よう＝良う

よう＝ましょう We discard this for obvious reasons

and other variants that I have learned like ように、ようになります、ようにしています、ないように、etc.

This is followed もの which I suppose comes from 物

And finally we have the もんね. I understand that もん is also a variant of 物, and a second translation of もん is that it carries the sense of exclamation or surprise

After much reflection I reached this conclusion I hope it is correct or I'm wrong and it has a different meaning

寮が個室だからこの学園選んだようなものだもんねっ Well, the fact is that/ the point is that I chose this school because it has individual dormitories.

P.S. sorry if my English is not very good I did the best I could. Un saludo desde México

Answer 1

You can break it down like this:

• 寮が個室だからこの学園選んだ "We chose this school because the dorm has individual rooms"
• ～様【よう】な "something like ～", "kinda", "sort of"
• ものだ "it's that"
• もん + ね "huh?", "you know", "hey"

ようなものだ can be translated as "It's kinda like ～", "It's almost like ～", "It's as if ～", "So to speak, it's ～", etc. This ような is "like", and もの is just a nominalizer. 寮が個室だ is not a great reason to choose a school, so the speaker "hedged" here.

The second もん at the end of the sentence is etymologically もの, too, but it is more like a sentence-ending particle on its own. It's used mainly by children/girls to convince/persuade someone. See this and this. ね means the speaker wants the listener to agree with her (and this probably means the subject of this sentence is "we" rather than "I").