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A former broom handle with a finisih nail driven in is my choice of weapon under the house. However, when the snake, the raccon, opposum, or sewage leak is encountered, I'm out of there.
I cut the hood of a rain suit and use it. It's hot, but I feel more protected. Shoes with velcro straps, no laces. I drag the fanny pack.
I do all the plumbing stuff first and note the locations of the A/C and water heater before going under.
I think I'm nearing the end of my "dig a hole for access" days. When I actually get there, I won't do crawls anymore. That is, if my girth doesn't stop me first.
