93 maxima timing belt

have 93 maxima w/vg30e motor, want to know if $705.00 is toooo much to get timing belt replaced. dude also said may have valve damage but wont know til belt is replaced. then how much friggin' more am i gonna have to pay

there are many motors with vg30,what is yours vg30dett~vg30e~vg30et or vg30i? in any case if belt has gone- lots of loot