TAKE ADVANTAGE OF
This can have both a positive and a negative meaning, but in both it simply means to take an opportunity.
When its positive, its taking an opportunity, usually financial, that benefits everyone.
When its negative, it means to take an opportunity, but by using another person.
You should take advantage of this 25% discount. At the party, she took advantage of the chance to meet new people.
He’s always taking advantage of his mother when he does not have any money. She always says yes. The insurance company totally took advantage of us.