I need a single bed

I am looking for a single bed or single room available for £400 per month. Ideally, the accommodation would be in a shared house or flat where I can have my own private space while sharing common areas with housemates. I’m open to locations closer to central London, including nearby suburbs, as long as the place is well-connected to public transport for easy access to my university. A friendly and clean environment is important to me, and I am hoping to find a comfortable living space that fits my budget.