@confuseddropout Of all the issues you are facing right now, this one is fixable.
You can PM many of us anytime with questions. Most will answer you. And at any step, post and ask, there are answers for you that will make this work.
First: your income is quite low and your situation is hectic right now. So some specific advice: go to your D high school counselor and explain the situation. Most HS have a fund for fees for those who can least afford them. Ask them to waive the lab fee or give her a scholarship for them.
Second: you should not have to pay to take the SAT or apply to many colleges. Ask about fee waivers. These little amounts add up, and you don’t need to deal with that. Period. The guidance counselor will help with that. Ask her/him also about questbridge. If the SAT comes up, it is a good way to ensure you can afford the ultimate choice. Ask about good teachers colleges in the state or that give good financial aid.
Third: this is doable. Breathe. Make a list and the two of you figure out how to do all the research. It’s ok. Let us know if you need help.