SELECT minimum value without a subquery
It seems that you want multiple bidders to be returned if there are more than one with the lowest bidderrate. 

In that case, you could use TOP with TIES

select TOP(1) WITH TIES  auctionid, bidder, bidderrate 
FROM [dbo].[Ebay] 
WHERE auctionid = 8211851222 
ORDER BY bidderrate asc;


DB&lt;>Fiddle based on your example.