Actually, minimum trading is decided by the trading site (one of the site from 0.0001B=0.7$ now)
When I trade first time, I exchanged about 550$ (1 bitcoin at that time, 1 year ago).
I realized that it might be a big chnace to earn big money at that time.
So I exchanged cryptocurrency a lot.

As far as I am considering to this situation.
Auctually, I sold half amount of my bitcoin, and bought bitcoin cash 50/50 2 days ago
Also I sold remiaining my bitcoin once and could buy lower price 6400$ again.
My bitcoin amount is a littele increased.
But if you can wait for a long time, I think you would better to hold it.
because many people says bit coin will be 9000$ in the near future.

No,I don't think you are late.
You can eran by swing trade or scalping, hold on 2 bit coins such as FX trading.