On occasion though I have had tenants that run into financial difficulty or other issues.

I've always considered myself all 3.activepassivebusiness I'm confident I could argue any of the 3 to my benefit with tax man etc, as I've done on previous occasions.

There are some rare occasions were I wish we had. 

You can use a set dollar amount or about 5-10% of collected gross rent.Landscaping: Depending on the type of the property, you may or may not be responsible for landscaping expenses, such as grass, bush and tree trimming and removal of leaves or snow.Utilities: In most cases, single-family home tenants will be responsible for paying utilities, but in some occasions you will need to pay them.

One habitually late paying tenant was so accustomed to including the late fee when paying that on the one occasion where the rent was on time, the tenant still included the late fee!

I've worked with house flippers on three separate occasions who tried to get more because their property had solar panels, but it never worked.

If there is an existing park, you may be grandfathered.A pitfall to be aware of with zoning laws - on occasion, I have run across zoning laws that disallow bringing in a replacement home once a home is removed or destroyed.

I've been listening to the BP podcast and on multiple occasions the advice is given to find a job in the field like being a property inspector, working for a contractor/subcontractor, or for other investors.

The only potential advantages I can think of -- You get the whole commission and don't split it with your broker- It's possible in rare occasions that you'd run into a deal that didn't want dual agency which could preclude an agent with that firm from writing an offer.

This sometimes breaks down if the tenant pays late and includes the late fees or on the rare occasion when they do not pay the full amount due but I have found it quite useful.