My second question is, can I take money out of their security deposit to pay for garden maintenance since they neglected the gardens around the house and didn't mow the whole yard.  

Then, include a gardener in your rent and require the tenant to let the gardener take care of the backyard.With a lawn, it's just a matter of mowing and weed-eating the edges, & leaf-blowing leaves into piles in the fall.  

I also like your idea of the gardening/landscape renovations! 

That's not to suggest that all of my backyards look like Better Homes and Gardens, but anything that's visible to the neighbors I try to keep looking reasonably good and expect the renters to do the same.

We offer garden space, too, and it's in a neighborhood full of green-minded tenants here.

And I earnestly would like to know what tools, out of all the garden variety of choices, are the most efficient to setup and scale my real estate business for the optimal performance.

Listing has become a real pain for most platforms because Zillow, the source of majority of the leads, is building a walled garden.  

The garden home one street over can only rent for $1800, and it's empty right now, and has been for 6 months.

I'm currently looking at the Old North End, Garden Ranch area (as close to UCCS as possible), and Park Hill.

The southwest area; Dr Phiilips, Windermere and Winter Garden are good for investing, as well as the SE side near the new Medical City (VA Hospital, Nemours, University of Florida Medical School, and Burnham Institute).