Sentence 1: Perry's new tech startup needed to get their computers ready. 
 Sentence 3: However, he probably should have been more specific 
 Sentence 4:  Sam brought the box of mice, but odd scurrying sounds came from it 
 Sentence 5:  Now Perry has to hire pest control & get a refund from the pet store 
 Option 1: So he sent Sam out to buy pet mice for the office to keep. 
 Option 2: So he sent Sam out to buy the 30 mice they would need in the office.