Translation:I will have to get mortgages to pay for the house.
I gave as my answer "I am going to have to take a mortgage to pay for the house." I submit that this is a correct translation, since to pluralise 'crédits' as 'mortgages' is not a translation, but rather, a transliteration.
It suggested "funds" also for "des credits" but then disallowed that translation when I submitted it. Bah!
"i will have to take out some credit to pay for the house"
That made more sense to me but it didn't like it.
Using multiple mortgages seems strange to me.
I wrote, "I'm going to have to take out a loan to pay for the house." and I received the message "You used the singular "loan" here, instead of the plural "loans". I'm wondering if in French this means to take out loans or a loan.
See my first comment. That is clearly the meaning, but duolingo didn't like it because we express the concept differently in English than in French. We would say a mortgage or a loan, but we wouldn't say credits, and especially we don't use the plural in English as it is used in French here. Hope that helps. You can always click on the left under the question and make suggestions.