Well, it depends on what exactly you want to clean. If it's for tiles, look for something that removes limescale. For sinks and faucets, a stain and rust remover works. People often ask us for universal solutions, but the truth is that you have to try a few to find the best one for your bathroom.
This is annoying, right? This usually happens if you don't rinse thoroughly after cleaning. Try using less detergent and rinsing with more water. Some people also recommend paying attention to the instructions if you missed them.
This is a problem, especially if you are sensitive to odors. Try to ventilate well while cleaning. Many people prefer cleaners with a more neutral smell or even those with essential oils.
You should generally be careful when it comes to children and animals. Keep cleaning products out of their reach and rinse surfaces thoroughly after cleaning. Some people prefer more natural alternatives for this very reason.