Thoughts on Contractor vs W-2 Mix in Regulated B2B Services?

I’m looking at a teaser for a B2B services business in a regulated industry. On the surface it looks interesting, but it seems like most of the staff are contractors vs W-2s. I’m still trying to confirm the mix with the seller, but before I go further I wanted to ask: for those who’ve been in contractor-heavy businesses, what are the real risks or guardrails you keep in mind? My worry is getting into a situation where too much of the value walks out the door if the contractors leave. At the same time, I don’t want to dismiss a good business just because of the structure. Curious how others here have thought about or managed this trade-off.