Being that current price of an L7 is 5,755 x 9.
I would like to propose a rather extreme idea based on overall investment and commitment level.
Following the trend of high dollar science. Do you own your house? If so, go underground. The insulation provided by dirt/Earth is un-matched. While that idea is very extreme, you’re already 40K plus into it. Underground the temps will stay consistent as heck.
When you consider the cost (electric) and effort to stay cool enough to run all machines 24/7, renting a backhoe, buying a international shipping container and hiring a on-site electrician (while building) is almost cost effective in the long run.
Even a smaller ‘bomb shelter’ type made out of Water tanks is within the realm of reality. 2 feet of dirt blocks gamma radiation, so you’d step out of the Sun’s and Solar Radiations reach.
It’s a pretty extreme idea. Maybe just building Earth up around your shed could mimic this method.
Or buy one of those Car ports, the plastic tarp and aluminum post kind (cheep’o type), Simply putting your shed in 100% shade may help. Those tarp/canopies are cost effective.
long url to Harbor Freight, that did not generate a link
If your local ambient temperatures are already hot, I can’t imagine more fans and air flow will do much
Another idea, that takes some imagination, is build your own radiated cooling system. This is gangbuster in indoor gardens, but problematic around electronics . sooo ‘imagination’.
Buy a cheep automotive radiator, preferable aluminum clean/new. Get a small aquarium pump (preferable 1-2 GPM, you don’t want a pump that generates its own motor heat). Build a reservoir out of a plastic tote container. Build a stand/frame out of wood. and jerry-rig some easy PVP tubes/lines (the kind you buy at home depot for 19 cents a foot, not some $40 super lines). Bury the Water reservoir deep in your yard (this keep the water cold). Run the pump/system using gravity, you just drop the water in the top of the radiator and it falls back to the reservoir.
Then add a fan behind the radiator. Or place the radiator where you Draw/intake air into your system.
In short the radiator cools air you pass by it, utilize that air flow and control it.
That could be done for about $150 (I’m guessing), and while it may sound lame or ‘not enough’. Every Car manufacture in the world thinks so.
There is also a product called an in-line water chiller. A professional version of radiated air flow in gardening uses the chiller instead of a reservoir. The chiller uses around 300 watts. So the radiated chiller system can run for much less than conventional A/C
And even these 3 idea’s combined, lol. Go under ground. Put a canopy over that area. and build a room or system that is just to filter/cool the intake air.