@Matthew Posteraro go with as many units as you can!

I bought 15 unit and have slowly crept up to 40-50 units. 

this works well if the tenant is a national user or multi unit operator who has built these buildings many times. 

 Which city in the United States has appreciated the most over the past 10 years?

If you make the purchase prices much closer, then the waterfront unit should do better.You are going to have to run the numbers.

The biggest things for our energy bills are: how many ac units are on the house and do you have a hot tub.

She wants to learn if it's possible to flip in the United States, remotely, and what that would look like.

my hope is to get a nice unit for my son at below 50% of retail.  

Quote from @Tyler Garza: Deal :Duplex Home2 beds / unit2 baths / unit3,000 sqftAsking 300k60k downEst rent/yr - 31,2005% Vacancy20% Op ExpenseMortgage 240k assuming 7%Results: CF - 6,600Cocr - 11%Cap - 8%Looking at this for a buy and hold and trying to determine if I am analyzing this right@Tyler Garza I can get to your COC of 11% and cap rate of 8%, but since I don't know your loan payment or amort, I'm not sure how you got to CF of $6,600 - I'm getting arond $4,600.And a couple of things jump out at me with your assumptions versus most of my CFO clients: 1) a 5% vacancy rate and 20% Op exp margin seem a little low, 2) an LTV of 80% LTV (with a 7% interest rate) seems high unless you're house hacking, 3) Depending on the location of the property, the $1,300/month/unit rent may be low.

In Dayton, I find most of my clients like A/B class 1-4 units because they can actually cash flow AND be in great areas.