Read up, get the tools and start climbing them yourself, no rentals,more in you pocket.
My "buddy" at work gave me a "deal" of $900 to take a 50 foot birch, ya some deal.
Got myself some spikes,harness,lanyards,and various ropes, took a climbing class,now I scare the s...t out of my wifesohigh up ...and the great adrenaline rush too.
I pay a helper 100 a day..a friend burns the brush in winter (few cases of beer pays for diposal.
\just a thought