keith wrote:

-snip-

Retrofitting exterior drains and interior would make such a remodel
prohibitively expensive and still not guarantee that there wouldn't be
problems. As AEM suggested, breaking the slab/footing connection
isn't a good thing to do. If you're going to insist on going this
far, sell the house and buy one that works for you.

Except this is alt.home.repair - not alt.buy-a-new-house.

Exterior drain could be as cheap as a couple shovels, a pick, a
wheelbarrow & 100gallons of sweat. [and probably a couple bottles of
naprosyn for the first week or two.]

The cost of a used elephant foot is advisable.

I rented a backhoe when I did the first half of mine. The next
section will likely be all handwork. It is only 25 feet long and
equipment will make more of a mess than it will save labor.

The point that everyone who has 'been there, done that' is making is;
don't waste your money on finishing the basement until it is ready to
be finished-- which means getting rid of the water under the slab. If
that means moving or abandoning the idea of making that space
livable-- then that is what you need to do.

Jim