I will definitely be checking the stringers for rot. I believe the ballast system is aluminum tanks, but the owner doesn't wakeboard and has only filled them up once according to him. What's so bad about having tanks rather than sacks? What if I could pick this thing up for $3000 or less then would that be a steal? Even if the stringers are rotten? I've seen pics of the tower and although looks homemade seems VERY sturdy and the weld job seems legit. Thanks for all the input! Keep it comin.