To camouflage stains in toilets use a colored toilet bowl cleaner that can be dispensed with each flush. Check any leaks or disturbing sounds. Organize cabinets and drawers. Remove or replace worn shelf paper. Remove personal items you don't want seen.
Buyers tend to snoop.
Bedrooms Keep them neat. Beds should be made and clothing put away. In children's rooms, it's helpful if walls and furniture are not cluttered. All are important considerations for a buyer. Attempt to remove unnecessary and rarely used items.