I preface this with the fact that I do not know if they have or use organic/non-toxic chemicals, as I just want the critters and pests gone asap. Anyway, we had a (ugh, it pains me to write this) "rodent of the Willard variety" in our basement last year and we called United Pest Solutions. At that time we signed up for a program where they come to our house quarterly to check for unwanted guests (in-laws do not apply) and spray for wasps, ants, spiders...you name it. They do a great job, are prompt and I don't think they're too expensive.
P.S. I do think the spiders are worse this year than they have been in the past.
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