46 acres of hilly woods in rural MO, surveyed sometime before 2005 for $3000. The plot has 3 straight boundaries that cross deep gullies, and the 4th boundary follows an S-curve of road. The previous owner had it done and asked that two extra pins be placed, one at the road and another at the back line, connected by a surveyed internal line, so that the halves had equal road frontage and equal area, 23 acres, though the subdivisions were never recorded and the county plat shows just one 46 acre property. These complications may have raised the price of my survey, but still I think your current $4500 for 150 acres is in line.