Diagnosis: name the damp before you buy
Most wasted spend in this niche starts with a skipped diagnosis. A dehumidifier, anti-mould paint or a salt tub treat different physics.
This cluster is the method: watch where the problem appears, measure relative humidity, estimate dew point, and only then choose a fix.
Guides
Damp at home: diagnose it before you buy anything
A step-by-step way to tell condensation, indoor vapour, rising damp and leaks apart. What to measure, what to watch, when not to buy a dehumidifier.
Rising damp: how to recognise it (and what not to buy)
Stains from the skirting, salts, crumbling plaster. How to tell it from condensation and when you need a surveyor.
Hygrometer: how to use it (and why it is the first purchase)
Where to put it, what error to expect from a cheap unit, how to keep a small log.