I tried searching for this in past posts, but couldn't find a simple explanation about what an A B or C property is. Can anyone give me a brief description of each or point me to a former post that explains it?

An "A" property is one that is located in a great neighborhood, housing good tenants and the property is in good condition. Like owning a Beverly Hills rental to high wager earners and the property has no deferred maintenance.

A "B" property is one located in an average neighborhood, but safe to walk and still low crime. The tenants are solid people making enough money to cover the rent and have a savings/retirement account. There maybe limited deferred maintenance but still is a nice place to live.

A "C" property is a lower class area. Some crime around the area. Tenants live from paycheck to paycheck with very little in reserve. The building is older and there's always some type or repair going on every month or two.

A - top notch; trendy, upper 5% income; best schools; ritzy & glitzy; recently built and/or remodeled every 5 years

B - very nice; everything middle class and up to semi-wealthy; built or remodeled in past 10 years; 3+ bed houses or loft apartments in downtown hipster-villes

C - average; 2-3 bed houses; 2 bed apartments; top of the lower class up to lower middle class; shows its age; lots of Section 8

D - scary but survivable, poor but generally okay people; retirees on limited fixed income; a few weirdos / and maybe a drug houses one block over; houses and streets look "tired", cops patrol frequently trying to keep it from sliding into F; Section 8 avoids because they can do better

F - death is no stranger; slums; da hood; cops avoid unless called to cart off a body; the people who live here don't want the cops because they all have records and/or have/sell/make illegal drugs

Everyone is going to have their own take. I call mine "solid C" as they are clean, safe, and functional, but may be dated. They remind me of the house I lived in during college that were simple and no frills. I was never robbed, assaulted, or had an run-ins with criminals for the 4 years I was there.

The “grading” of properties and tenants. Is something that someone came up with in the last couple of years. It is a bit loose in definition (as you see there is a bit of difference in the descriptions above), but helps us on this website in discussing tenants and properties.

Robert and Sid gave good descriptions on this.

At one point, we were using a realtor who was schooled in residential (homeowner) type properties, rather than investment properties, to find new properties. My husband gave her the instructions we were looking for B or good C properties. She was fairly new at the game, and did not understand what we were looking for in a property. She thought we were trying to discriminate against tenant, and got all bent out of shape.

That's when we started looking on our own, and just eliminated a realtor to help us find ones in which to invest. Unless real estate agents are experienced in working with investors, they are pretty much useless.

6x6 - depends what the property owner is looking for. In my area:

Lower than C have rents CONSIDERABLY higher than you would think (because the tenant's don't have other options but do have a cash flow)

Maintenance is basic, minimal or nonexistent.

The downside is the buildings themselves are worth very little unless someone decides to buy everything up and redo the entire block/neighborhood.

Sorta Blonde, you asked: I wonder what a Landlord of an F property would wear to do inspections?

The question may have been asked tongue in cheek. My guess would be that very few landlords of F properties do regular inspections.