What size must a retirement plan be to get Vanguard recordkeeping?

For a 401(k)-style retirement plan to get recordkeeping services at Vanguard (not Ascensus), what size and other conditions must a plan meet?

Any anecdotal information would help me.

Thank you for your neighborly help.

The minimum is generally $50M in assets. I think they will discuss opportunities if your plan is close to that amount and has good cash flow. 

Thank you, this is wonderfully helpful.

Is $50 million in plan assets enough? Or, must it be $50 million in Vanguard funds?

My understanding of their recordkeeping requirement is the $50M minimum could be invested with any fund manager. 

Again, thank you for this helpful information.

Last time I looked at their website they were only offering various IRA's, SEP's and 403(b) services.  I don't recall seeing any minimums, but I did not think they were doing any other type of record keeping without going through Ascensus.