I have a lot of investors who like new build homes because they are built to code, they will fix everything on the inspection report, which typically means it will be a very headache free investment for many years to come.

So, create status codes for both of these and a few in-between codes to help you work smarter, not harder.

Send them the lock code in pre-check-in instructions and at time of check-in (because not everyone reads the full message first time round), and automate a "how are you liking the place?"

David Greene makes a video about once a quarter on the BP podcast showing how to do this and usually he gives out a discount code for BP premium.If you need the MLS do you have a friend with access that you can do comps with?

I would not trust an average number.This will be very specific to your management, your lease, your leased property, the area etc.Some people have made money, but I've not heard much about arbitrage lately, and some have lost money and  not honored their lease.In general this is just a job and not an investment, so it's widely discouraged in this forum.

The investing and the tax code works for the LONG HAUL.  

"Code box" sells lockboxes that change codes for every showing.

The real problem is that the vast number of beginning investors never bother to learn their state landlord tenant codes before they invest.This is my pet peeve with new investors...trying to operate a business requiring knowing the law without having the desire to learn.They should never be allowed near tenants, they need a PM.On the other hand responsible investors that learn the laws first I would strongly advise self managing.

Just because you don't make any money on them, doesn't mean you aren't responsible, along with the source of the actual plans, for any mistakes in the plans, or even any mistakes in construction from lack of info, misunderstanding, or just plain stupidity of the builder/user of the plans.The licensing agreement will have guidance on having plans adjusted for local code, reviewed by architect/engineer etc. 

You will need to contact the city Building Dept to ask if there are any city coded you must follow.Or, hire a qualified Property Management Company.