-1 to having a stranger wander through your place and things while you're not at home. As a commenter on this site you should be well aware that any computer security precautions are forfeit when physical access is available.
Get a roomba.
Get a roomba.
Hire a maid.
Nobody said allowing access to the helper while nobody is around. Weekend help for a few hours is a thing. You can rest and relax while they are around. Just don't be dumb enough to tempt them by leaving a purse full of cash on the table. Even the best of the people can fall prey to a moment of weakness.
They quality of the work eventually went down. Fewer nooks and crannies were cleaner each passing week, there were also "cleaning mistakes" that happened that led to a roach infestation happening (or not being prevented from spreading), such as wet dishes inside the pantry.
I just moved to an smaller apartment and will just clean it myself, maybe will ask my GF to help me out.
For domestic work, you usually can't offer them a career progression path to keep them interested. So the alternative is rotation. Though trust is definitely an issue, if your location has maid agencies that arrange for this kind of work, that aspect can be mostly addressed.