If you're purchasing vacant land you should perform a feasibility study and determine what type of septic system can be installed. This way you'll know the approximate cost to install a septic system.
Here are a few septic design companies we have worked with in the past.
Address: 2971 Phillips Lake Loop Road Shelton, WA 98584
2. Arrow Septic Design
Address: 171 E Vuecrest Dr, Union, WA 98592
Phone: (360) 898-2255
3. Peninsula Excavating Inc
Excavating contractor in Mason County, Washington
Address: 2380 W Highland Rd, Shelton, WA 98584
Phone: (360) 426-4364