Hi Devin,
As far as new construction, as long as the numbers work I have no opinion on new vs old- however would keep in mind if converting to a rental if the property is in an HOA the dues will be coming right out of your profit. Even though you're planning on selling the property in a few years, I would run scenarios in converting it into a rental. Since the market is pretty hot in Charlotte right now, I think it's best to be prepared for either scenario with a new purchase in case things change (which their are mixed opinions, but it can't keep up at this pace forever, and you can't time the market).
There are three types of real estate investing models, and it depends which strategy you're aiming for. With the higher end home (+$200k), you're aiming for appreciation and proceeds on the sale of the property. These properties typically will not cashflow as much as lower-end homes ($50k-$150k), however will appreciate at a much greater rate. If your goal is to hold the homes for the long haul and cash out eventually then the numbers may work. However, if your goal is to cashflow and maximize supplementing your income, I'd pursue a lower priced investment home. Personally, I aim for the $125k-$165k range as I feel it has ability to appreciate and cashflow (try: Mint Hill, Matthews, Stallings, Belmont).
My hesitation with the higher priced & larger homes in Charlotte is you're concentrating your risk into one property. Much to the tune of why investors love duplexes, having your risk spread between properties is beneficial to ensuring profitability when things go off plan. In addition, the 2,900 sqft home Capital expenditures is not included in your cashflow above, which I would figure once all said and done this property may not be as profitable as you're calculating. Once you factor in at least one month vacancy, maintenance repairs, all capital expenditures (accrual on monthly basis), I would bet you may change your perspective on converting to a rental. In addition, the $1,200/mo mortgage is quite a large risk if you're placing your trust in one tenant to pay. If you for some reason have a bad tenant, vacancy, etc. this mortgage is coming out of your profitability and it's a lot to be on the hook for in my opinion. On the same note of markets, you also have to be flexible to cut your rent if circumstances change. In bad markets, you'll find renters trading down to the less expensive homes and $2,000-$2,300/rent is a hefty sum in a bad market and you won't be the only one in this scenario. I'm not very familiar with areas closer to uptown, but the reason I've stayed away is due to all of the construction and massive amounts of apartments being built.
My recommendation would be to spend some quality time with the numbers and plug in some other rental models. I would also not necessarily trust the realtors opinion out right, do some digging to find out what comparable homes are renting for (zillow, craigslist) and how yours stacks up. Calculate all of the benchmark metrics (1% rule, 50% rule, Cashflow (this includes capex & operating expenses) Bigger Pockets has an investment calculator on here, though I made my own excel spreadsheet to manipulate some of the inputs as well. I'm happy to share the template if you're wanting. If you're interested in checking out my neck of the woods, I could also give you an example or two of homes I've found lately that I would consider or at least plug in to compare against your primary home.
