This is just my method and it works well enough if you want a clear cut way to do something: Score each section honestly with 1-4. 1 being the best, 4 being the worst or vice versa... doesn't actually matter (for the sake of this, we'll do 1 = best). After each area has been scored, add them all up and divide by the number of sections (areas). whatever your number is will give you at least a fairly close guess as to what it is. 1=A, 2=B, 3=C, 4=D. If you do it on an excel spread sheet, you can always add more criteria later on for grading and will always have a template to evaluate other properties in different areas. Lastly, I generally grade two areas instead of just one whole. Building class and neighborhood class. The building class could easily be an A or B if it is super old but entirely rewired recently, newly remodeled, etc, versus, a new home can still be terrible with no updates and be a D. Evaluate what traits you consider to be a generally accepted as desirable and undesirable and write them down and do the scoring of 1-4 for it as well. overall rating should be lapsed because if there is even a single three when everything else is 4, it will never be a four if you don't stagger the numbers. 1-1.74 = A, 1.75-2.4 = B, 2.5-3.24 = C, 3.25-4 = D.
To reiterate, there should be a class rating for: (this is an example of one of my properties)
The neighborhood
1. Age of community: 4 (100 years old)
2. Things to do: 1 (clubs, golf, movies, shopping, bars, parks, river, mountains)
3. Scenery: 1 (mountains, river, trees)
4. amenities: 1 (Park, pool, river, football field, tennis court, baseball field (not close enough to be hit lol), yard)
5. crime rate: 1 (literally only a few assaults in past year and one robbery)
6. income: 3 (median household income = $43,000)
7. transportation: 2 (some but not much)
8. walking distance: 1 (close to everything)
9. ***Personal rating of overall neighborhood: 2 (nice neighborhood but just not a class A which is really nice)
10. ***Personal rating of the neighborhood's buildings' condition: 2 (very old community but well kept victorian houses and overall well maintained).
4+1+1+1+1+3+2+1+2+2=18/10=1.8=B
And the property you are looking to buy: (This is when I bought it, not how it is now)
1. Age: 4 (1923)
2. upkeep Interior: 3 (nothing super messed up but needed a lot of work)
3. upkeep exterior: 2 (Old and needed a little work but overall looked nice)
4. electrical: 1 (new wiring, service, breaker box, etc)
5. Plumbing: 2 (newer but may need work in a less than 10 years)
6. appliances: 4 (there were none)
7. room size: 2 (fairly large but not huge)
8. curb appeal: 3 (overall nice look for an old brick building but meh, nothing special)
9. unique features: 2 (Cool architecture and design)
10. amenities on property: 2 (has a ton: big yarded area, tennis court, etc.)
4+3+2+1+2+4+2+3+2+2=24/10=2.5=C (barely)
Ultimately, don't get too wrapped up in the class rating. It is more or less for you and every single last class rating in this WORLD is going to be subjective to the person rating it. Take it with a grain of salt and just use it for a quick reference. If they are asking $500,000 for a fourplex and its a C class neighborhood and C class building, I would probably keep looking, but in my case, a barely C class (almost B class) in a B class area for $5000 and less than $20,000 in repairs and renovations, it was a no brainer. I'm not an expert in real estate, but I do think in numbers for most of everything and it hasn't failed me yet. Good Luck to everyone who reads this and I hope this helps some.