Ummm...I find it hilarious someone who lacks basic reading comprehension and critical thinking would advise someone to be smart...Not sure what the point of your rambling posts about depression are about, but you've detracted from the thread enough, please stop before I report you.

Once in a while you see a BP success story about someone's first flip, and power to those folks, especially the ones with comprehensive "lessons learned" sections in those narratives.

If you focus your time enough in small enough area you'll start to get a pretty solid understanding of what's normal for rents.If you want to be really comprehensive you can then compare against local property management listings and then have them give you an estimate.

If your intent is to branch out into managing properties not owned by your investment group, this will require further investigation.The key to managing 100+ units is to develop systems for accounting (or purchasing property management software), using forms vetted to be effective in your jurisdiction, and developing a comprehensive policy and procedure manual.  

I did my lease through Rocket Lawyer which seemed pretty comprehensive, but I will have to go back and review the eviction section of the lease just in case. 

Cities and Towns have studies and use some of their Planning Department's time in order to develop an overall plan for how the City/Town will grow and what locations have certain uses (i.e. residential, commercial, industrial, etc.)...this is represented in a Future Land Use Map (sometimes also called a "Comprehensive Plan" or "2030 Land Use Map"...you get the picture).  

Try this company: http://commercialrealestateinspectors.com/multi-fa...They've provided a very comprehensive 55 page inspection report for another commercial deal I was involved in.As far as 30-40% expenses in LA/Long Beach, it is not what I've generally seen in my underwriting.

Its a simple and short read, I encourage you to check it out and then move forward with a comprehensive plan/checklist for exactly what you are seeking.

.- Should we make a comprehensive written guide for each feature?

Just make sure you do a comprehensive screening of them and as long as nothing alarming shows up, I'd say you could go for it.