Very few 172's in this country would be over 15,000 hours, 182's most are under 10,000 hours. A few 206's I know of are 20,000 hours +.
Most cheap 100 series Cessna's are in need of paint, engines, interior and SIDs.
Do the maths! (engine 35k + fitted, paint 15k, another 10k to fix the corrosion hidden by the paint, interior 7k, windows 3k+, cables, SIDs, replace the c*#p avionics, seat belts) Before you know it that 25k "bargain" owes you 150k.
Plenty of 2000 and on model 172's on TAP starting at 80k so why would you bother??
http://www.trade-a-plane.com/search?...-seq=4&s-lvl=0