Use your $30k for down payment or initial rehab but budget extra for unexpected repairs.Your lead methods (D4D, DealMachine) are strong.

I texted her the rent amount on Tuesday afternoon (per her request) & the various ways to pay it - she said she would "get with me on the payment". 

This will still qualify for a residential mortgage and you have a better shot of completely offsetting your entire payment.

I would avoid any tool that charges 1% of booking revenue as payment.

Let’s break it down.Moving to Your Next HomeYour equity could help you cover the down payment for your next home.

Even if their Renters Insurance company wanted your insurance info, an insurance represetnative would be contacting you for it.7) You haven't stated if the tenant is current on their rent or withhold rent payments?

so those owners are pretty comfortable - no mortgage payment - and they don't need to sell, and they don't care where an investor "needs" the price to be to make money. 

I'd look at the closing docs for something related to the pro-ration of expenses etc and see if you have anything there that could be a clause you point to for them to cover those payments. 

I’ve just heard horror stories from landlords and I’m looking for suggestions on how to best vet tenants - Good credit, no missed rental payments in last 5 years, etc.

Generally, lenders will require you to have a substantial down payment.