The horsepower of the pump doesn't matter as much as the depth of the well. It takes considerably more time and bigger equipment to pull and set a 500' deep pump, as it does a 50' deep pump. Also there is a big difference in time and equipment needed between steel pipe and poly pipe. $100 maybe too much for a 50' pump on poly pipe, while $1,000 may not be enough for a 500' pump on steel pipe. Give us some specifics like a 1 HP pump, 200' on sch 80 PVC, and we can get you a better number.