He said to just put at the highest setting and change filter more often filter cost is honestly nothing for Airbnb hosts.

Should I provide my guests with bottled water or a Brita water filter or leave it up to the guests to bring their own water?

I am not able to locate the filter for multi unit properties.

I am working on a tool to analyze EVERY deal that comes on the market and filter it down to only show you the deals that match your specific buy criteria (residential only for now). 

These typically include services like renters insurance, HVAC filter delivery, pest control, and sometimes utility management.

Paid platforms often offer additional features like market analytics, off-market property leads, and filters for investor-specific criteria, giving them a leg up over free options.Exactly, most platforms have to offset cost somewhere because of how expensive it is to keep the data up to date.

I think it's great as it includes warranty information for appliances, type of hvac filter, light bulbs and general maintenance etc 

There is a filtration (basic ) in thee garage that came with the house when I purchased, but the filter gets rusty in about 5 days.

By all means give them a note on how to use all of the appliances (eg clean out the lint trap on the drier after each load, do not use dish soap in a dishwasher, change the furnace filter regularly, etc).

One of them hired a landscape guy, well, the landscape guy never came so I was paying $140 per month for nothing for about 7 months.The other property manager didn't tell the tenants they were responsible to replace the ac filter, that bill was $1000 to replace the AC fan motor.I am really afraid of blowing off the money.