Then hands me her business card, "call me, I can help you." 

A property manager not requiring this raises serious red flags.

It's likely a scam anytime they sound like AI or the grammar is weird or they use the word "kindly", if they ask for you to respond to them off-platform, if they say their employer will pay for it, if they ask if the dates they've specified are still open (when they can clearly see they are open on your calendar), if they ask for a video of your property (they probably want to set up a duplicate listing with your photos and video and scam others out of money), or if they want a long term booking and they have just joined the platform and have no reviews (could have been evicted from somewhere else, and hope a newbie will let them in with no background check, they'll end up not paying or credit card is bad).  

Those old homes are such a wild card! 

One of my clients had a $1M deal under contract where they needed to do a $300k raise. 

Probably this. california department of Real estate has already nailed two agents for raising rents above price gouging thresholds.. 10k fine plus who knows what kind of license discipline.

At the moment with 3 rentals (6 total units), I have one account and a credit card associated with it.

Raising the rents will not be as easy as merely sending out notices of rent increases.

Leaving the area for the sake of real estate investing isn't in the cards for us.

After several months of hard work, I was able to raise the value of the home.