With some staging and paint, we were able to sell our previous personal residence at a small profit, and use the profit to leverage 3 more properties: 2 as investments, and one as our (downsized) personal residence at the time.

I like that the market hasn't recovered too far from the GFC but with the aggressive incentives for business and jobs coming to the area, it feels like an area on the cusp of a Stage 2 Buyer's Market.

Also keep in mind non-rehab related costs such as holding costs (utilities, taxes, mortgage payments, etc) and selling costs (commissions - typically around 6% total, staging - if applicable, etc).

I'm in the final stages of buying my first rental.

I recently heard of a conference with top real estate executives that had a panel of 5 millennials.The millennials sat on stage and these executives asked them questions about where they eat, what they do at night, where they want to live, etc.How often is everyone taking millennial activity into account when making investments?

You can either update it more, stage it with modern furniture (remove family photos, knick knacks) or drop the price.

Is it too early in the development stages to invest?

I think that you have well intentions of investing some money into this vacation rental but perhaps it needed to be allocation towards professional photography and more staging guides. 

(Unless if you buy in LLC or trust, but I am not at that stage yet).

My guess, is that at this stage of the cycle and with the positive growth that Atlanta is seeing, these properties are in D class areas.