Should I get a septic inspection and additional questions

[Jack B.]

A handful of items I'm curious about on this house purchase that I'm adding to my portfolio at a 50-80K discount:

-The house has a septic system. Should I get a septic inspection as part of the purchase? First time dealing with a septic system on a purchase.

-The seller wants to remove the clause that they will clean the house and remove trash/rubbish from the house. They left the clause that they will take their personal belongings. Considering the deep discount, I figure I'll pay 1K at worst to remove trash they leave behind. Thoughts?

-There is an easement for the neighbors driveway that runs through this property. 

-That same neighbor has been paying this sellers well fees for a while. Should I get an agreement in place before closing as far as maintenance fee split for the well?