Where to host an Auction?

I’ve started planning for a new Dynasty League and want to hold an Auction for the startup draft. The only site/app I’ve used for Auctions is ESPN and it was terrible. I plan on using Sleeperbot App for hosting the League and they don’t (yet) support auctions. Suggestions on a Site or App that is good for Auctions?

Optimally, multiple players could be bid on at the same time with the ability to shorten the timer the deeper the draft goes. I know MFL is pretty customizable, but it’s quite unattractive and I don’t really want to pay for a season just to host the draft.

I turn to the Footclan for advice. Thanks!