Monitor problem!!!!I have acomputer but my monitor is not turning on is it fixable?

I am having a problem with my computer everything is working except my monitor. It won't turn on anymore nothing comes on at all not even the lights on the botton it's a HP monitor do you think it's repairable? Should i just buy a bran new monitor? Also If I decide to sell the whole computer how much do you think i can get for it if the monitor is not working??? Someone answer these question for me!!!