So far it has been a little over six months with an average net income of $350+ a month.

I imagine Airbnb (the company) has their own wifi.Wifi router just takes the incoming internet signal from a modem (cable or otherwise) unless you have a combo unit.If you have a hardwired incoming internet cable then you can use almost any wifi device.

After that, offers are typically made through an online offer site.

Or rolling that profit into another property(s) to obtain more rental properties to increase monthly income?

Getting a degree is not totally necessary but one that can bring income is good like engineering or computer tech.

I never bothered with logging my time (because it was a hassle and I didn't think it would be much benefit) but now I'm realizing that I can't contribute to my Roth SDIRA anymore because all my income is passive.

We also looked into Ron LeGrand's course for creative finance, the price was nice however, it seemed a little outdated (now we may be wrong).In an ideal situation, we would like to spend $5k or less on the course, online, with the chat-bots or a call-in line for questions with an extended expiration date to ensure my business partners and I have enough time to thoroughly study and take the course and also have the opportunity to re-visit if we have more questions later on. 

She came out of a recent divorce with close to $1M liquid and a credit score in the 800's, has history as a successful GC/landlady, but after liquidating her previous rental properties due to divorce 2 years ago, no longer has recent income.

Is it possible to use the projected income of a str property built in 2024 and use that income to help qualify for a heloc on another property

If your city has these laws, I would find a way to check each month to see that your tenant is paying those utilities - checking the account online?