Another Wet and forget fan here, good for killing miss and that green coating everything up here in the sunny northwest gets covered in. It’s also supposed to clean stains over time. I’ve found it good for killingvtge moss and green, not so sure about the stain removing claims but pressure washing seems much quicker now and stuff seems to stay clean longer. I like pressure washing but I’ve destroyed various concrete slabs with a pressure washer so if helps reduce that I’m happy. £36 for 5 litres from Amazon, you dilute it 5 to 1 water so it goes a fair way.
For weeds you can’t beat Glyphosate (Roundup) for safe, effective and relatively environmental impact (it breaks down very quickly and isn’t harmful to mammals despite what the loons in California think, not good for aquatic life though). It can be a bit slow acting as it destroys all of the plant including the roots. The fast acting weed killers tend to be nasty chemicals that burn the leaves off but allow the plant to regrow from the roots. Any homemade weed killers are technically illegal so don’t.
Steam and weed killer burners just destroy the foliage allowing the plant to regrow quickly from the roots.