Nobody should quote a wall they have not looked inside.
A small hole and a borescope answers the four questions that decide the job: is there anything in the cavity, what is it, how far up the bay does it reach, and is there staining or damp on the back of the sheathing.
From that we can tell you whether the wall wants filling, repairing or leaving alone, and what band of the assessment-stream rebate it is likely to fall in. Holes are plugged and made good.
If your house was built after about 2000 the cavities are almost certainly insulated to code and a survey is unlikely to earn its keep. Spend the money on the attic and the rim joist instead.
Barely. One small hole per area of interest, plugged afterwards. In siding we go in behind a course so nothing shows at all.
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Book an attic check
You get the depth, the tier, the dollar figure and the photographs, whether or not you go ahead with us.