You have to be very careful choosing keywords as Google can quickly get people to your website.....but not the right people.
I wouldn't personally suggest "Hard floor cleaning in Birmingham" this is purely because a customer would rarely call their floor a hardfloor, they would normally be searching for something like Oak floor cleaning in "Birmingham" for example.
You need to be quite specific, you want quality clicks not quantity of clicks.
Think of your past 10 customers, how would they have found you searching for you based on the work you carried out.