Try and get your hands on a small scrubber dryer vacuum. They only hold about 5 Litres of water but they are the size of a vacuum cleaner so easy to store and much more efficient than any mop and bucket. They range in price from about £200 up to about £1500 but they are ideal for areas around 20-70m2 ish. What you have to make sure is the brush bar is motorised! You would be amazed how many of them aren’t and rely on you pushing and pulling they are essentially only a carpet sweeper with a water vac. VAX are the biggest culprits for these although their latest one advertised does look like its motorised.