He who has the Gold makes the rules.You want to talk to people who have money about "Private Money".

And if this were the case, $25/month would not come close to compensating for the possible costs associated with a tenant's pet.Obviously there are ways to protect yourself from liability regardless of the source, like LLC status and a good umbrella insurance policy.

I am thinking to install a wifi smart lock on the front door, so guest can come in the front door with a digital code.

You don't treat the rental operation purely as a business because you live there, eat there, sleep there, have social guests over, spend personal funds furnishing/decorating it, use the same space your tenants do for carrying out the activities of your daily life, etc.

What if they do, but the guests hate each other and fight over the bathrooms, etc? 

Feel free to attend your first meeting as my guest.

There are fewer than 50 properties in a renovation status waiting to be marketed for rent.  

Or try and emulate websites that you know convert, there have been a lot of podcast guests that have websites they use to get leads.Sometimes if your website is too slow it will cause people to bounce as well, that's another thing to check. 

Does anyone have a short term rental contract that they make the guests sign before renting a property on airbnb, vrbo, or anywhere else?

A quick search on Airbnb shows many guest/back house available to stay in.