Adding to what Greg said, there are lots of buyers who aren't pre-approved or will make an offer and then not be able to get financing wasting the seller's time.

Quote from @Errol Sadler: Hi BP community,I’ve successfully added a second story to a home in Atlanta and am now exploring whether this is feasible in Fort Lauderdale, FL.

Flipping and other value adds is where the experienced investors are or if they are holding it likely is a development effort (such as adding a dozen ADUs).Good luck

Not sure where the ad litem attorneys stand in all this. 

I see some hosts doing an "I forgot" box and adding that to their listing photos.

It is possible to buy too many too fast and put yourself in a financial hardship.Have you ever heard of a startup store that done real good and added another store that done good?

Transitioning to a Second Property with Low Money DownIf a second FHA loan is not an option, here are alternative strategies to minimize your out-of-pocket expenses:Conventional Loan with 5% Down: Once you’ve added equity to your current property, consider refinancing into a conventional loan to free up your FHA eligibility.

Most hit all the bullet points excepting:Spending $175 on renovation and adding square footage or unit count does NOT miraculously convert to valuation.

I added 5 properties this year. 

See my long list posted earlier of the issues adding an ADU.Good luck