Finally a HELOC will most likely show on your credit as a revolving debt so it will be classified in the same category as a credit card.

I referred to it as a revolving foreclosure market in 2006 when I was appraising.

While you may only be saving $10/day, I think it's good business and good practice to keep revolving debt as low as possible when you have the cash to do so.  

The success for his second and third options both revolve around you being honest with the lender and they are aware that the first deal is in the works.If you are up front with that information, you can find a work around such as what Chris listed.

I was wondering if anyone had any recommendations for the best software to help with accounting, tracking rent payments and CAM costs?

If you blow out a cam on the IKEA box, you are screwed.

The credit line is also revolving so once you pay the funds back the full amount of the credit line is accessible, which IMO is a HUGE positive for using those funds for rehab costs or down payments. 

These three tips revolve around three words.  

Then use 45%-50% of gross rents (GR) as your carry and maintenance costs (CAM).  

Most of our work revolves around budgeting and variance analysis, however we also do a lot of capital and operational modeling that draws heavily on the company's financial reporting.