Taking college courses in high school will not hurt chances of admissions or scholarships for when a student enters college full time. The key is that the student needs to maintain their dual enrollment status as a high school student. The biggest scholarship opportunities are when a graduated student fully enrolls in college and that's a one time thing so you want to save that for when a student enters the college they intend to graduate from. But, students shouldn't fear taking college courses in high school.
And, yes, whether or not you can transfer the credits will depend on the college you attend. Most highly selective colleges won't grant credits. That isn't to say if a student intends to attend a highly selective college that these courses were without value. They may still be good for: 1. keeping the student busy and engaged during high school. This is not a minor point! 2. for admissions purposes by demonstrating the student sought out challenge. 3. for placement purposes even at some schools that won't accept the credits. 4. For actual credit if the student decides to attend colleges or universities (and that would be MOST schools) that accept transfer credits.
