If the house is so old that it has ancient pipes that have never been serviced, or massive trees all around the house that could have roots burrowing into them, etc, etc.

I'm rooting for you to get out of the rat race soon!!

Visio has a solid financing product for STR's 

I have solid credit and good cash flow.

I'd also recommend when trying to contact the owner you do so after gaining a pretty solid feel for what the home is worth or what an investor in your area would pay for it. 

I am ready to purchase my first few properties in Chattanooga.I travel to Chatt fairly often but would like to have a more solid feel for the area in terms of where to place my first investment, I am currently looking in Red Bank.Though I don’t plan to rent immediately..I will likely house hack for a year (ideally with a MIL suite or basement) and rent it out afterwards while I then focus on getting a stronger foothold in wholesaling.

Option #1 sounds good.Look at your Option #2:You have already planned to wait 4 months to save 3k on your current REFIYou are increasing your pool of cast at 2k per month, a projected +8k growth in your cash pool.If you put your cash on that pay down, you say you will save ~1k  (equivalent to 1/2 month) and you take your self out of the market for your second investment for 4 or 5 months.Just be sure to hold your horses for a new investment that has solid cash flow and not be depending on current appreciation rates.Your focus on REFI makes me wonder?

I will be turning 18 in a couple of days  I only have 4 months of solid work experience so far, what is another way I can obtain a pre approval letter for hard money with limited history in work, and no experience in real estate?

Your father did you guys a solid and everyone should benefit.

I'd like to develop a solid business plan but to honest I'm not sure where to start or what all to include in a well formed business plan.