That's quite surprising..According to NameBio, there were 9 L.top sales in 2017 and 2018. They were between $161,000 and $218,000. They were all reported by Jiangsu Bangning Science & Technology Co.,Ltd, which is the sponsoring organization for .top domains.
Always impressed by your so called appraisals lolJust pulling a few random single-letter .top sales reports, none of them are developed and most don't even resolve. Some are parked pages or landing pages. I wouldn't trust the sales reports to put value on yours, as they appear to be manipulated and not valid with no end user development in sight.
$50 to $190 = Reseller Value Speculation (NOT an end user speculation)
If that is really true, which I doubt, it's worth 150k minimum. In reality it's worth about 2k if that isn't really true