We are in Ohio and rehab a lot of houses with septic systems, we put in 30+ systems in the last eight years
We replaced six last year and three this year already. In our area typical costs are 8,500-9,500 for an off lot aeration system. We have had numerous quotes in the past and use one main contractor these days that does good work at a reasonable price, if you get three quotes you will likely find them coming in between 8,500-12,000
For small city lots, or other lots with soil that has bad drainage, in our area we put in off lot airation systems. County determines what they will allow, but these are the cheapest in my experience.
For an area with good soil, if putting in leach lines you should still be under 10k . If you have a large lot say an acre or more and they require a mound or drip system, these are more expensive, most we paid for one of these was just over 14,000
Age of tanks is important to take into consideration, I was told by couple septic contractors that life expectancy of a septic is 30 years. Although if in an area with good sandy soil they may go 40-50 years with out much problem. If in a very clay area and you have leach lines could be less then 30.
You mentioned septic under a driveway 20-30k repair . Something seems off, unless it was under a roadway that you had to build a temporary bypass for traffic and had engineering requirements that added a major expense. New system should be about 10k and a driveway repair, under 5k . But there are unique situations.
We had one recently that required off lot discharge for a new system, and no acceptable discharge ditch on our property. It required engineering to go across a small street in allotment, building a new temporary road so fire trucks could get into the neighborhood during construction, etc etc. About 10k extra. We originally figured 10k for system 3k extra to go across the road. We ended up getting the county to approve an on lot discharge system and it cost us just under 9k for everything.
Hope that helps. Good luck.