What kind of features: security cameras, electronic gates, shipping/packing materials sold on site, easy access to many local living spaces, etc?

I like the search features: https://www.biggerpockets.com/search

I was listening to the Bigger Pockets Podcast featuring Ashley Hamilton.At the 41 Minute Mark(Here), she says that she purchased a property through yearly tax auctions?

Again, there is nothing better than a software program on one computer where you don't pay monthly fees, you have the ability to customize it and it has every feature you need.I never said I did not try apps.

Make adjustments to the comps for features, size, finishes and things like backing a busy road, this should bring the range in tighter.

What features of storage parks help generate customers?

I’d be tempted to try and design an attractive feature on that exterior portion.

No fussy features like marble countertops that stain easily or other house systems that require upkeep like water softener systems and similar. 

There are some softwares out there that are inexpensive and are specifically designed for small portfolios.When you add in the online rent collection and tracking of expenses and some other features they are almost always worth the cost in my opinion.

When I say free, the bread and better is free but there are side features that cost extra.