You're in for a shock at the cost. Find out why it needs pumping as if designed and working properly they shouldn't.
The biggest mistake is people putting grey water into the septic when it isn't big enough and wasn't designed for it. Also if lots of soapy water ie washing machine dishwasher lots of showers baths etc can stop the soakaway working as it clogs/seals the floor with a soapy water resistant cake and it then just back fills all the other chambers.