I'm told that Section 8 are such sticklers and make demands of landlords for simple things that like toilet seats and knobs on stoves being repaired. 

I've spoken with PGW (utilities company) and I have a general understanding of how the process would pan out (i.e. hire a contractor to split the lines, make sure new BTU amount is serviceable, and then call PGW to add the new meter). 

Here are just some of the things I'm referring to:Pool/Jacuzzi maintenanceFireplace maintenanceWood Flooring maintenanceIndoor Appliances (Dishwasher, Oven, etc)Outdoor Appliances (AC units, Grill, Firepit, etc)HVAC maintenance/inspectionsLawncare and sprinkler system maintenancePluming issues (toilets, sinks, etc)Water heater replacementsElectrical issues(lightbulbs, ceiling fans, etc)...the list goes on!

Drain I can keep since I am within the 3 toilets per drain rule here. 

I am thinking of turning one unit of a duplex in Indiana as a short term Airbnb rental.I have a question: What percentage of your income goes toward expenses such as cleaning fees, commissions, insurance utilities, supplies like toilet paper, etc?

It was updated in 2019 (New kitchen- shaker cabinets, stainless appliance, granite, new toilet, and vanity in the bathrooms). 

The rest of the house was functional, so there's no point in putting them up in a hotel.In your case, the tenants couldn't use the toilet for one day.

Have you included STR specific insurance, furniture, pots and pans and dishes and all kitchen implements, linens, paper products, etc. and all utilities including internet and cable? 

One of the tenants in my duplex poured a tray of lasagna down the toilet resulting in sewage backup and $450 worth of remediation.

For example, on one of our properties, we installed all brand new low flush toilets and reduced our water bill by 55%, a massive swing in usage.