This is based on the anticipation that the property will warrant that higher value upon reappraisal/sale. 

What's the formula on what one should pay in renovations considering the purchase price and anticipated sell price? 

Account for seasonality in your numbers to come to a final anticipated profit figure. 

Both were purchased around 5 years ago for cash & have both cash flowed & appreciated more I had anticipated.

So if you hold long term you will probablY catch the wave and reap higher rewards than anticipated. 

As of now it is still a sellers market but there were ALOT of loans that did not trade that lenders are looking to get off their books, so I anticipate loan pricing to soften slightly.

I can anticipate the markets but I CAN"T CONTROL THEM.  3.  

We are anticipating our first real estate investment on the outskirts of downtown Memphis.

So you'd just have to factor that in and see if it would work for your particular scenario.Also, regarding them factoring in the anticipated mortgage on the new property, it's probably too late now since they've already processed your application and factored that in, but in the future if you put that the reason for the HELOC is to "have cash reserves" then you won't have this problem. 

I calculate the cost to get the property, my anticipated rehab cost, and my holding cost to get things done.