My advice to you is don’t cheap out on a sprayer, I use them for work and most of them are shite, tried b&q ones that have split, others that uses cheap rubbers that break down when coming into contact with chemicals.
One thing to look out for is Viton seals, they last a lot longer than normal rubber seals and can withstand chemicals.
I can personally recommend the kale sprayers
https://mosskillers.co.uk/spraying-equi ... n-sprayers
They last ages, I leave them with sodium hypochlorite in and the seals are just fine, if you want a decent manual sprayer I’d get one of them, if you want an electric sprayer then you want the big boy 2, it’s not cheap but the thing is a beast
https://windowcleaningwarehouse.co.uk/p ... al-sprayer