The lowest LLL.net sale in the past 30 days was TVQ.net which sold for $722 on January 25, 2016 at NameJet. There was another one JUY.net which sold for $810 on February 18, 2016 at NameJet. Then several more that were neither Chinese premium nor Western premium that went for right around $1k. I think the first two were flukes, it seems to be around $1,000 to $1,250.
The average LLL.net sale last week was $3,062 which is down from the previous week of $3,322.
Here's a quick link to the LLL.net sales from the past month sorted by price ascending:
https://namebio.com/?s=gN4YzN0czM
As for NNN.net there were only 10 sold in the past year so it is harder to say. The last one was 489.net which sold for $7,150 at SnapNames on January 24, 2015. Before that it was 045.net for $5,001 on January 15, 2016 at GoDaddy. I don't think either of these would be considered high quality NNN.
But then in November of last year 755.net sold for $2,500 at Sedo, and I would consider that a high quality one because of the repeat. And in September of last year 238.net sold for $9,130 at Sedo. June of last year saw 072.net sell for $2,465 at 4.CN. These are all pretty old in such a rapidly changing market.
When they sell this infrequently it's hard to say what the minimum, or even the average, is. It seems to be somewhere in the mid $x,xxx range though. Here's a link to all NNN.net sales we recorded in the past year:
https://namebio.com/?s=QO0czN0czM