Bathrooms.. no extractor fans

[Eqei]

Recently moved and neither bathrooms have extractor fans… the ceilings look like they’re definitely being affected by this and I hate that we have to open the window ALL day - still doesn’t seem to make a huge difference.

anyway, my questions:

• do they need to be professionally fitted? If so, by which tradesman?
• is it better to get them in the wall or ceiling?
• any recommendations ?

I recently had my main bathroom renovated and it previously didn't have a fan so I got one fitted.
Definitely needs a professional electrician to fit. Mine had to update my fuse box too as the bathroom wasn't on the RCD. Probably best to speak to a local plumbing firm or builders. They will also need to drill a core hole in the wall for the output. I was lucky mine didn't need scaffolding!
I don't think wall or ceiling makes a huge difference.
Should be possible to get done in a couple of hours depending on complexity.