On asbestos, I recently remodeled/gutted/rebuilt a 1934 house. Floor tile (and tile adhesive), plaster board, mortar and plaster were all suspect. Sampled all of it, bought test kits from Amazon and mailed them all in.
You really can't tell just by looking at it. Sample and test for the win. Floor tile and adhesive would be two things I would consider first.
Furnace gaskets? You bet. Asbestos was the wonder material back in the day. Fireproof, indestructible, insulating properties, additive for adhesives, etc.
Its when you sand it, grind it, expose it that you can get into trouble. You can only imagine what a home rehab can involve. Fortunately, 1934 was kind of early. for asbestos. By WWII it became common, and continued into the early 1970s.
People often ass-u-me that asbestos was all about insulation. It was in so many other products, from automotive brake shoes, corrugated siding, on up.