If they report that the maid cheerfully does everything they’re asked or shown, on a continuing basis, but nothing else – you should be ecstatic.

Showing up on time is important. If they get through your checklist early – you don’t care. Your needs have been met. More likely they will not get through everything, but both of you will know what needs to be done next time. Does she have ideas about the status of a maid or the propriety of cleaning someone else’s closets? If she is afraid of being thought a thief if she opens a closet or drawer, she is never cleaning the dust bunnies that accumulate there.

Exceptionally slow work may be bad news.  Proper cleaning of a room takes a long time. You need to know that she can do a room or two thoroughly and still have time to do a minimal swipe at the rest of the house.

The maid may already be so overscheduled that she’s exhausted. Determining her availability for a trial period may give you an idea of how booked she is. If she has a lot of clients with small apartments, she is going to be spending a lot of non-paying time in travel.  That time has to be made up with more paying clients. In other words, visiting five houses in five days is better than five houses a day, even if they are all in the same apartment building.

Is she is taking the job of a maid to earn money until she gets another job (an actress? A semi-skilled dress-maker’s assistant?) You don’t want to take the time to train the perfect maid to lose her to another job.

Sometimes the reason your friend is recommending her maid is because your friend is not happy with the maid but doesn’t want to leave such a nice person without a job.  This may be OK. Make arrangements with your friend to ‘go on vacation’ and loan you the maid for a week or two. At the end of the trial she can go back to your friend, grateful that she isn’t working for you, or you may have found someone you can work with. The maid may also start doing a better job at your friend’s house.