Try going on a "break" with that realtor and look specifically for one who not only understands investments but who also has good technical acumen for exporting and doing deep analytics on the MLS data. 

fwiw, I am quite proficient in Excel (have some experience with data analytics, pivot tables, formulas, macros, etc.) so I could likely easily manage a small database of leads by myself just with Excel…and create my own dashboards etc. but anyone using something in particular that they enjoy?

If you like to get nerdy with analytics then you'll likely find that you are more optimized with the HELOC versus cash,  but that's really not super important at this stage. 

Haven't gotten too deep into the costs yet, but doing the preliminary analytics. 

@Christopher BrownI would agree with @Joshua Strickland, it depends on the market on how accurate the analytics are.

The more important thing is to trust your analytics.

Question - what are the best software packages that can calculate short term rental analytics? 

I'm an ambitious and analytical young investor focused on developing a portfolio of cash flowing SFH and small multi-family short term rental properties in North Florida. 

Looking forward to learn and use data analytics for better investing. 

If you want to look at an ARV from a future potential investment value from you renting it out, then you would need to find rental comps as well as investment sales comps to go with that rent to project a value off of NOI.It's going to be hard to pull comps without some sort of data source like Costar or Crexi or Real Capital Analytics.