I am an Executive in a life sciences company which takes the majority of my time and I have no intention of stopping that, but want to build a larger rental portfolio to have other financial / lifestyle options in 10 years. 

I need someone's help to help analyze deals and to more or less tell me which to execute on.

Has anyone ever successfully executed a deal to close on a condemned property that is planned as a fix and flip?

That's from executed contract, not including visits, tours, negotiations and holidays.

I saw one flawless project where the investor exited with like 40k profit in like 90 days. 

I got a property with clear upside potential.Over the next 12 months, I executed a systematic value-add strategy.

Clark,Excellent question, and thank you for asking it directly.My reasoning is simple: at this stage, single-family and small multifamily deals are well within my current execution capacity; I can source, underwrite, renovate, and manage them with a high degree of control and minimal outside dependency.Larger apartment complexes, however, require a different level of capital, operational sophistication, and speed of execution that far exceeds what I can reliably deliver alone today.

I want to execute a cost seg on both.

Quote from @Elealeh Fulmaran: Shahab, start with these three that turn theory into action fast: 1) The Book on Rental Property Investing by Brandon Turner for clear numbers, deal anatomy, and beginner-friendly frameworks; 2) Real Estate by the Numbers by J Scott and Dave Meyer to level up underwriting, sensitivity checks, and real-world decision rules; 3) The One Thing by Gary Keller to lock your focus so you actually execute your first deal instead of dabbling.

Quote from @Kresimir Lastric: Hi everyone,I’ve been following the convergence of blockchain and real estate for a while, and I just came across a project that I think is executed particularly well.SmartDeeds is launching fractional membership interests in “Project Malibu” — the concrete oceanfront estate in Malibu designed by Pritzker Prize winner Tadao Ando (previously owned by Kanye West).