The house I'm trying to sell is a rehabbed old farmhouse with a 2-ft
thick field stone foundation. It's really quite nice ... except for
the basement.

My first question is: How solid are these things? The house was built
100 years ago. I don't see any evidence of settling - no cracks in the
living area walls. No stones have fallen out or even moved inward into
the basement. Potential buyers are sure to ask this question.

My second question has to do with water seepage/leakage.

In non-wet weather it is constantly damp down there. There are 3 open
casement windows but they don't have a lot of square footage.

In wet weather, water comes in through several places. In very wet
weather there is one spot where it actually pours in like a faucet
turned half-on. This was not a problem until the city put into new
sewers out front ... but alas I didn't file a complaint.

The floor is dirt and has a dry sump hole about 3 feet deep with
natural gravel below. That's where the water exits. But the whole
basement still gets wet and damp.

I don't believe there is anything I can really do about the water
entry. The outside perimeter of the house is slanted away from the
foundation and my gutters take roof water to the streets. The house
just sits at a low area in town and I think that's the problem. It was
wet down there from the day I bought it in 1987.

I have some ideas I'd like to bounce off you. There is a fourth window
now boarded up. I'm thinking of installing a fan there - like the ones
used to pull out radon gas - that runs permanently, venting air to the
outside.

I'd also like to put a liner in the sump hole and put a pump in it
that pipes water out to the street.

I'd like to install a dehumidifier with drain into the sump.

Although the fllor is damp, I'd still like to try to dig a channel
around the inside perimeter than drains water to the sump, but I don't
want to go too deep because the floor is level with the bottom-most
layer of fieldstone and undermine the strength of the wall.

It looks like back in the 70s someone tried to solve the problem by
pointing the whole inside wall with cement. It apparently didn't work;
most of it has fallen out. I believe in my case that water pressure
from the outside exerts far more power than any sealant can handle.

In wintertime it is fairly dry (upstate NY) down there.