I think it would be better had you broadened it to 'servant'. Because a maid is most often a feminist term.
Look out for middle-evolutions. Second stagers. Most of them rightly have the build of an able Pokémon. A first stager (note - most cases) would be either too small or too tiny to be exploited like that. The third stager would be too strong and valuable to set around doing chores, don't you think?
Psychic types, like many suggested, would be really good help around the house, doing mild stuff that requires some amount of concentration. Kadabra, Kirlia, Gothorita and the others, you know. Fighting types like Machoke could help with the heavy load, the storehouse and the attic. Water and Grass types for the lawn and garden? Roselia, Lombre?
Though if you think of it that way, certain final evolutions can also be included in the list, a very good one being Mr. Mime, Jynx, even.