First time home buyer, looking to buy an investment property in New Orleans. Looking to buy a double, long term rent one side & Airbnb the other side (due to laws in New Orleans, doubles make the most sense for Airbnb purposes). 

Background: I have been pre-approved for up to $500k but am looking to buy in the $250k-$300k range. There are places to be bought at this price, I have an Airbnb income model to help me calculate cash flow (I am open to other models you may have). My rate is 4.625% on a 30 year FHA (could also do conventional if needed).

My Dilemma: Cash to cover 1) closing costs 2) down payment 3) furnish the Airbnb side of the double would be around $30k on an FHA and $85k on conventional at $300k purchase price. Monthly expenses project to be around $2,300 and I am estimating that I can bring in at least $3,000 in rental income ($1,300 on the long term side and $1,700 on Airbnb). Rental income is a conservative estimate.

The two options in mind (feel free to enlighten me to other options) revolve around the FHA $30k cash. I can sell 11 shares of Amazon stock to cover the cash needed and buy the property now or I can save up $30k over the next 12 months (definitely do-able for me) and put a down-payment on a property with saved cash.

Pros/Cons that have come to mind in no particular order: 

If I wait to pay initial costs with saved cash and kept my Amazon shares:

-I would avoid paying long term capital gains from selling 11 Amazon shares, estimated $5,000 in taxes (pro)

-Interest rates could rise in the next 12 months requiring me to need more than $30k in cash for the FHA/buy a more expensive property (con)

-Housing market could keep inflating over the next 12 months requiring me to need more than $30k in cash for the FHA/buy a more expensive property (con)

If I sold Amazon shares now and purchased the property:

-I could lock in an interest rate and refinance in the future if rates go down (pro)

-I would start gaining at least $700 per month in cash flow over the next 10-11 months (pro)

-Amazon stock could appreciate over the next 12 months while the real estate market could depreciate  (con)

-I would incur about $5k in long term capital gains from selling my Amazon shares and I would also miss out on any future appreciate of those 11 shares (con)

I tried to keep this as short as possible while including relevant info and things on my mind. I am prepared to hold this rental property long term. I would love to hear advice/pro-tips and lookouts for things I may not be considering.

Initially it seems it really boils down to performance of the housing market vs performance of Amazon stock but maybe I am oversimplifying it - I will greatly appreciate any and all feedback!