It will need to meet all fire and safety codes per your local building codes.Done properly a secondary unit in a SFH is the best method to generate positive cash flow on a otherwise underperforming asset..  

My summers were 1/2 gone before they started because of schedule commitments and you miss a ton of nights putting your kids to bed. 

Get a good contractor and factor in permits (the city knows it has had a fire) proper remediation and rehab. 

Unfortunately, there are too many medical professionals that are broke because they haven't properly managed their money and assets over time. 

Here I was cringing everytime it rained, but thinking I was gonna skate through unscathed....NOPELast night I got the phone call from my property manager...YEAH...UM...YOU NEED A ROOF...I knew it was marginal, and  I was hoping it would make it, but NAH.It's getting fixed today or tomorrow...Hopefully all the tenant rights advocates will praise me for my quick action!

I send them a final email the day they arrive and try to troubleshoot problems the moment they come up (smoke alarm was beeping last night for our current guests but I told him to press the right button to stop it). 

They might not code the expenses properly or do not know how to maximize profit and have to constantly rely on a CPA.

No one that has given you proper advice is "thick". 

Thrya,Congrats, let me know if you need any assistance for the accounting aspect.First, put each property in its own LLC and open a bank account for each LLC.You do not need to create an LLC for Property Management, you can, but it's not necessary.You need to make sure you have the proper Chart of Accounts such as Assets, Liability, CapEx, OpEx, G&A Exp, and Equity.Chances are you will be putting the majority of the expenses under CapEx since you're renovating, once it becomes rental, the expenses will be OpEx.

Avegail Tizon is hosting a Cash Flow Game Night on the 18th which might be of interest to you.