@Martin970
In my opinion, you can get over a bad review or appease a guest with a small gift card or something like that, but you cannot find a really good housekeeper. In fact, I think a housekeeper who treats your house like her own is a treasure and if it were me, I would let her burn a little sage, what's the harm.
I had a tenant who believed in burning sage and as far as I understand it, it is burned to clean bad energy left by a malicious person. My tenant believed that bad intentions of the person lingers behind them and brings bad luck or something like that. When the tenants above her unit left, she wanted to sage the whole building and I told her to go for it 🙂
It actually does not smell bad, it dissipates in a couple of hours. Let her clean, burn sage and run an ozone machine for 45 minutes before the guests check in you'll be fine. If no ozone machine, then leave some windows open run the fan. This reminds me an old credit card commercial. A gift card: $25, an incense $5, a good housekeeper/cleaning person: priceless
Just my 2 cents.