Double room ideally with en-suite wanted.

I am looking for a property within 20 minute drive of Amersham (where I work as a teacher). I am looking for a double bedroom ideally with en-suite but not a requirement. I have a car so would need a parking space.
I need to move out of my current rented flat as my flat mate is going to live with their partner in our shared flat. The tenancy ends at the end of July so I would need to move by then. There is a possibility I could move at the end of June but would need accommodation secured to make arrangements with my current flat mate.