I'd write a letter to the LL asking him/her to purchase a dehumidifier, and notify him about grading so's its on the record....
Even a small one at $130 with a gravity drain hose is better than nothing.
40-60% is normal range I believe. Above that, you can really feel the moisture.
Windows will have to be kept closed.
That area is foggy all the time but very beautiful. I've driven Road 9 a few times twisting through the trees.
If you have suspicions about types of mold, you can get inexpensive test kits at Lowes and maybe HD.
This might be grounds to cancel your lease early if necessary.
I've had black mold in an apartment (in my 30's), and woken up not being able to breathe!