Hi everyone, I've been approached by a friend who's 8 year old interlock driveway is starting to sag in the tire tracks and starting to look bad. The same company did 27 of the 81 houses on his street within a year of the houses being built. Now they're all looking bad. Basically its a 25x40 driveway with a walkway coming off it. I'm guessing since the driveway is so new, the base is crap meaning i'll have to go down a good 8" and correct it. My question is, should i replace the base material or re-compact what's already there? Also, what do you guys quote for a 1000sq ft driveway? Thanks guys! I appreciate the help!