Hi, Recently my parents asked me which is better :- they had to replace a "broken" cable box. The provider offered them one for Rs 1000. They would continue with regular monthly subscription of Rs 300pm. Or they could pay Rs 3600 in advance for 12 months of programming and get a "free" replacement cable box. I think the bank interest rate there is about 12%. How BEST to think about this problem? What is problem framework for an easier answer? Thanks.