Thank you both for your thoughts. I've never seen this before so I was a little baffled.

The house is in France and my mother is thinking about retiring there, it's for her. I live over the border in Switzerland so it'd be easier for us to see each other. She's pretty specific about the area she wants to live in and some other things, so the search is pretty much within one neighbourhood of one city. And she's picky about how the inside should look, so it's always made more sense for us to buy run-down houses and fix them up after we move in. We've done two before but never anything with structural problems and we don't want that.

So under the French system there are lots of legally required inspections and legal searches, and we were planning to hire an English speaking inspector anyway too. Seems like the sooner, the better!

I realized after posting btw that the basement rooms against the garden (instead of pavers and a party wall) are the worst affected, so french drains probably would help. I've just never seen efflorescence before. I looked at our photos again and it's not as bad in the prospective house as that photo I linked, but it's still there...

Thanks again!

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1983 300TD 240k Thistle Green Auto (Euro) [sold]
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