Plugging EMSL Analytical for DIY asbestos testing - double bag your sample in ziplock bags (sample only needs to be a square inch or two), fill out a Chain of Custody form, and mail that to your closest EMSL lab with a 1-2 week turnaround time (it will be pretty cheap, definitely less than $50, probably closer to $25). Check the box for PLM EPA 600/R-93/116 (<1%) or PLM EPA NOB (<1%), for VCT/mastic use the 2nd option. Their website explains what the different testing methods are so based on the material you need tested you'll need to select a different way to analyze the sample.

Or pay a 3rd party to collect the sample and submit it for analysis - the takeaway is that asbestos is no joke and you should confirm it is present (or not) before any type of demo (hopefully not abatement).