Marketing & sales here.
Lots of good advice in this thread so far.
House cleaning is ultra local so focus on driving your happy customers to review you on Google (make it really easy for them; QR code, link, clear instructions, whatever... just ask for reviews).
Social media like IG and FB could work for this type of business as well, since you can use local-signal hashtags (neighborhood, city, generic keyword, maybe one custom hashtag that helps you position your brand as unique). Normally "post to social and hashtag, get more reviews" is a basic-bitch marketing 101 comment that doesn't really affect the bottom line but it's extremely effective for local businesses. Just don't post transactional garbage like "get X% off", "cleaning is important, book now!", "it's international mop day". Post funny, interesting, personable things that subtly show -- from the old pickup phrase -- amused mastery.
I just hired a move-out cleaner in my area and I found that most people didn't have a searchable website that was well indexed on Google (eg. "house cleaning {my city}", so then I hit up Facebook with the same search. After I checked for a few decent reviews that stretched back a few years, I started emailing people.
The first lady that replied sent me a 3-sheet page of homework ("I can only quote you if you give me all this info"), I was in a hurry so I ignored her. All the rest of the people replied a day or two later, sloppy emails/messages, vague quotes, trying to address pain points I didn't even bring up, or just being annoying. I remembered the first lady -- in comparison to all the others she now seemed serious because she was insisting on the hurdle of hearing my actual requests before diagnosing them (powerful positioning).
Sure enough, once I filled in her form she replied promptly, we discussed expectations and pricing, and then when she came she did a fantastic job. After I paid her invoice via e-transfer, I immediately got an auto-responder message to please review them.
If she can find and keep staff long-term, she will be able to take over whatever cleaning demand exists in my little town, no problem.
EDIT: I don't know if this is an issue where OP is from, but where I live everyone knows about and talks about how all staffers now churn super fast and when they do stay on to work they make fake sick-day excuses to take Monday and Friday off (so Fri-Mon "holidays" each week). If I were doing cleaning I would advertise that when you book, no matter what, the booking gets honored and if the owner has to come themselves and scrub your windows/toilets they will do it. Doesn't matter if you never planned on having staff and you and your wife (the owners) are the only workers. Just get ahead of the narrative that the current staffing issues will not affect your service. Or if your town is not experiencing staffing issues then find out what the local issue is and craft a pithy narrative about how you have solved it for your clients.