There is a wide variety in the types of costs attached to different septic tank systems. But no matter how cheap or expensive is the tank system you have decided upon, your final bill for septic tank installation will be idiosyncratic to your property or dwelling. For instance, if your dwelling sits on an elevation, it may not need a pump system to move effluent through your tanks. Conversely, depending on the topography of your land, a pump system might be required even if you opt for a cheaper tank. In general, tank systems that include extra wastewater treatment or sand filtration systems cost about one and a half the basic septic tank systems price.