@Polat CaglayanI've never seen a formula but here is a general rule of thumb for multifamily:The class of an apartment refers to the quality of the building, which can be determined by a number of factors, including age, location, and condition: Class A: These are the highest quality apartments, typically built within the last 15 years.

Regarding a book, I learned a lot from Location, location, location by Ozzie Jurock and he has quite a bit of free content on YouTube and his website.

If it's in a good location anticipated to go up in value, it could be worth it

Your location, your list, your approach, market conditions, time of year etc.The only thing I can tell you with 100% certainty is you'll need to SMS a lot more people than you will need to cold call.

What location?

Conveniently located just minutes from the interstate, this home offers an easy commute to Bangor and Newport, while Etna Pond and its public boat launch are just a short drive away.

With $1mm cash we can do 3 locations netting $40,000 before income tax per month.  

Do you remember the name and location of the senior complex you toured?

You want to be close to RTP (our economic hub) and the airport (located right by RTP).

Learned that I needed a realtor that was local to the property location.