I'm going to hire my significant other for a cleaning service job.
Why do you want to hire your significant other for this job?
She's very good at cleaning and I know that she'll do a good job.
I know that your significant other is good at cleaning but both of you are expected to keep your place clean and tidy. Partners need to share the responsibility and not put it on one person. Paying them to do your share of the work is not appropriate.
She's a damn good cleaner and I'm going to pay for her services.
That would not be good for your relationship with her if you treated her as your cleaner. You should hire someone  professional if you don't wanna clean your place yourself.