1985 CivicTiming belt Failure?
 

Hello, Im new to this forum, but not new to cars. I own a 06 subaru wrx, and am looking into purchasing a 1985 Civic 4wd 5 speed. I want it for a daily driver. (i commute close to 100 miles a day and need to keep the miles on my car low.) The owner said that the timing belt broke, and he doesnt have the time to fix it. My questions are, how hard is it to replace the timing belt? How likely is it that the engine was destroyed when the belt failed? any information is appreciated as i am new to hondas! here is a link to the add let me know what you think!:D

honda civic wagon 4wd $600