No credit card required
Browse credit cards from a variety of issuers to see if there's a better card for you.
As far as I am aware, installment loans do not greatly effect your score, other than their tradeline effecting AoOA AAoA and/or AoYA and in a smaller part inquiries. I mean the balance remaining to initial balance does a bit, but not as much as the rest.
Why do you feel like your score will plummet?
If they did, every student would be in trouble. for example I have 100k over 16 loans. Got 2 new ones each semester. Never took more than a few points off when I got them.
CCs are a very different beast, so don't sweat it.
Installment debt won't clobber your score at the level that credit card debt will. I suppose that's because credit card debt is a "help yourself" situation. In contrast, each installment loan has to be cleared by a computer and/or banker and fit comfortably into one's income and budget.
My biggest score gap was 616 Auto8 and 694 Bankcard 9 (TUs). An Autoloan 30d late was erroneously on my account, and it affected auto8 a lot more I guess. I think I've heard of 100 point gaps. Not sure about larger ones, but certainly possible. My largest "clean" gap is about 40 points.
Even though it's installment loans being added, I would think that adding 150,000 debt would have some kind of negative effect on one's score since it would increase risk.
OP, would you keep us posted on this as I'm curious to see.