This is a great point.
I do think rent should be factored into credit and I hope the industry does head in that direction. You could make the argument that it's not a line of credit but if it were my house and I were letting you live there, that's extending quite a bit of good faith. Not precisely credit but similar exchange of something that is mine for a payment you will make me later based on your written agreement to do so. I would imagine that as far as statistics go, one's ability to pay rent on time every month is fairly predictive of their ability to meet other such obligations in a timely manner.
Just my two cents.
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