@Pierre-Sebastien Beauboeuf you may want to consider variation of a conventional loan called a homepossible.

@Patrick M Nichols I'm not an attorney and you are, but it seems to me that the plain reading of the words is that selling, transferring any property (and all the variations thereof) when you don't already own the property (i.e., for another) is a license-required activity. 

Each state has variations, so consult a local attorney if you want a reliable answer.In many states, you can get the best of both worlds: create an LLC for legal protection and then make that LLC taxed as an S-corp for tax purposes (if justified).When you're starting out, you do not need an S-corp for taxes.

I've not bothered to get licensed outside of California because just within California is plenty enough regional variation for me to keep track of...

If selling the property, I would make sure the listing had the Appraisers square footage listed, note the variation in the Agent Remarks, and provide proof of additonal SF to any potential buyer. 

May need a zoning variation or special use.The zoning district may impact you for example the district might be approved for commercial use even though it currently is residential.  

question (or a 1,000 variations thereof).  

I had tried about every variation but the correct one. 

Every time I've had bids on plumbing I've been surprised at the variation.

I have used several variations of rehab calculators, including one we modified and have been using for several years, but I really like the new BP calculator.