water stain

My shower leaks when in use. I rubbed the wall dry, the water has stained it (see second photo) . For now i just want to smear some waterproof sealant over thew stain on wall. Any recommendations? Don't want to spend over £30 ideally . Thanks

Hi all, we have water stains above the windows in our bedroom. The bedroom is a converted loft/attic so the windows are slanted Fakro. The stains have been there since we moved in, and when we moved in the previous owners had left the windows open from at least June to end end of august (when we...