Not so much a question as a comment...
I listened to The Money Pit this morning (Oct 15) on AM1260, The Pledge, in Holland, Michigan. A woman called in asking about waterproofing, and Tom and Leslie said there wasn't any need for expensive treatments. My response is a resounding...maybe.
You focused on the fact that the woman's home doesn't have gutters, but I didn't hear you ask some other very important questions such as:
How fast did the flooding reside after the rain stopped?
What is the level of the ground water in relation to the basement slab?
What is the fill under the slab?
Is there drain pipe around the perimeter of the house and a sump crock in the basement? (Probably not in this case, but ask.)
Is there drain pipe under the slab routing into the sump crock?
The answers to these questions are just as important as whether a house has good, well-functioning gutters that route the water away from the home. No amount of gutters and top soil sloping away from the house will reduce the likelihood of flooding if the groundwater elevation is higher than the basement slab elevation. And, at least in the state of Michigan, there is no uniform requirement for the basement to be above the known high groundwater, and it seldom is checked unless the house is being built in a flood plain. There are a lot of houses here in the Holland area that were built by unscrupulous builders, while public officials turned a blind eye, and sold to unsuspecting homebutyers during "dry times," that were "sitting" in the groundwater in 2008-2010. While maybe not always necessary, I strongly advise every prospective buyer to have the property survey include an elevation of the home relative to groundwater. If only I knew then what I (painfully) know now...
Brian Douthitt (rhymes with "south-it")