On a boat of that age there are many variables, the boat could be worth between $1000-$3700. First off you didn't state the length but I will assume that it is either a 16 or 17ft boat. Is the floor rotted out, do the electronics/accessories work, what is the condition of the seats, does the hull have many dents, does it have a trolling motor, what are the age of the batteries, does the engine run (how's the compression, What is the condition of the trailer (bunks, guides, steps, wheels, tires, frame), etc. I buy and sell these boats all the time and a Bass Tracker of those lengths with rotted out floors/decks (fairly common) with a sound trailer and engine would bring about $1700-$2000. If it has sound floors/nice carpet/all electronics work (basically a water ready rig) it will bring between $2700-$3200. If the boat has been what I call reconditioned new floors, carpet, seats, nice options (autopilot trolling motors, fish finders, etc.) will be worth more (these are the boats that look like they just came out of the factory and need absolutely nothing).