you agent is mostly right..

any property can sell as it is, and if the seller does not live there, he is not require to sign a disclosure form.

as far as well and septic tests, they are not requirements for mortgages.

usually you test the well for water pressure and bacterial contamination. water pressure lower than 40lb, you may have a leak, that can be an expensive item, bacterial is easy to treat, basically just put chlorine down.

septic test is not too important, normally it just tell you is the septic functioning or not, but you can almost tell from the age it the system, its life expectancy is 20-25 years, if you need to replace it, cost is about 3k for gravity feed system, or 7k or mounted system.