Lastly, should I continue collecting rent through Venmo or should I have her set up automatic payments with my bank? 

Because of bedroom sizes and the septic system's limitations, we limit it to two total.You are not automatically violating Fair Housing by limiting (or increasing) occupancy standards.

In Delaware a lease automatically rolls to a month to month lease if no renewal is signed and 60 day notice is required to vacate (or to give notice to move)  If you prefer to have it vacant in the summer then give her notice to move and not leave it to chance. 

A couple of days ago, they took an automatic payment from one of our tenants!

Like I say to everyone, 87-88% is the number for automatic acceptance. 

I would guess in the near future you'll start to see meters that automatically shut-off after excessive use.

For example, if the tenant reports their refrigerator isn't working, the system automatically responds with some troubleshooting tips.

Any company that won't show me pricing is automatically very low on my list.

People on these mortgages had their payments go up automatically with every interest rate increase and saw cashflow completely wiped out.

I mean say if I include in the lease contract something that says "any rent later then the 1st of month shall be considered violation of this lease and this yearly lease shall simply become a weekly lease (as weekly leases I read only need 3 days notice to evict) from when a 3 days notice is automatically needed to be considered with per day penalty being $100 if not moved within 3 days of non repayment of rent from the date of not paying (due date) the person's presence on the property shall be considered illegal and will be treated no less then a violent intruder".