If you have a number of ice chests or large styro-foam food shipping boxes, you could bag your snakes & put them into the "ice chests" in garage. Be sure you
don't crowd them or over-lap bags. If you need more warmth, a bottle of hot water will do it, as will ice water if it's too warm. I'd open them about every 8 hours
for fresh air & to change water if needed; not sure how well your lizards will like this idea, but probably OK for them too? I've had to do this for moving cross country
as well as for long power outage (ice storm), all my snakes were fine & stayed healthy...didn't seem to faze them. Sure is safer than pesticide exposure, good luck.
And incidentally, the flea nightmare you're having is why my dogs are on Nexguard...fleas are not an option for my house, & they're spread easily when our pets go outside, from roaming cats & squirrels as well as neighbor dogs. Some areas are much worse than others. When I lived in So. Calif. the more populated areas were awful (with fleas) but in the high desert (with no close neighbors) fleas were non-existent. How I miss those days...(no ticks either).