Guerilla Marketing tactic would be to print a bunch of business cards > in large quantities they are quite cheap like 3 to 5 cents per card. Go to Air BnB, see all the properties, then go to them in person and stick your card on the door or somewhere obvious that they might see it.

Let's link for a marketing meeting

Have you optimized your Google My Business profile? Practiced any SEO? What partnerships do you have with businesses or associations in San Diego? These are all questions I would pose before making any suggestions. Also curious where you get the majority of your clients now and look for ways you can increase that! Look forward to connecting!