I just went through the whole application process and they even appraised it only to tell me I have to own the property for at least a year before they can do this deal.

A few bucks for the post and a few bucks for a galvanized post base will be structurally sufficient for pretty much any application.

How long did it take to fund from when you submitted an application until you received funds?

I would not accept any applicant with a score below 650 or one with debt. 

But "a guy from Home Depot" probably didn't take your Visa as a payment and likely isn't running his own S-corp.As far as filing, you might consider this as the year to get a CPA involved with your taxes.

I am a newbie investor who really can't offer any advice on investing, but could certainly help with with value add opportunities as well as ways to potentially maximize your bad debt collection from those residents who you had to evict or who have skipped out on their lease.One of the best things I recommend an owner does with their residents is to get multiple emergency contacts on their application.  

But from there applicable agencies create rules, and then further guidance memos on the law and it's rule.

Since this is FHA loan, I learned that FHA loan number assigned for this property need to be moved to new lender and unlike conventional loan application, I cannot have 2 lenders working on same property at a time? 

The dog duplex could be profitable if the market is right (pet ownership is over 50% in many areas, yet fewer places allow them)...I would either try and market the duplex as  a dog-friendly unit (with the separate yards) and give full barking disclosure and even invite the applicants to come by at various times to test the noise themselves; or (especially if my dog friendly marketing wasn't working) I would cycle the existing tenant out, remodel and go with fresh tenants of your own choosing.Best of Luck....

It would be ok to say you are looking for a particular ROI IMO.The only point I am really trying to make with regard to defining what a "good" CAP rate is is that you can lose a boatload of money on a high CAP rate property, and you can make a boatload of money on a low CAP rate property, and visa versa and all points in between.