There's been a lot of talk lately about BTC going up again, however I'm not here to speculate.

Let's say BTC jumps to 5k per coin, and even small-fry BTC holders like myself, suddenly have 5-6 figures worth of bitcoin. What do we do then, if we want to sell some for fiat?

When dealing with tens, or even hundreds of thousands of dollars worth of bitcoin, how can you actually safely conduct a transaction for that amount of money?
I don't even feel comfortable using something like Coinbase with ~200$ USD in BTC, let alone trusting them to not cause any fuckery if a single BTC was pulling 5k$ or more.

I've seen people mention going to the deep web to sell, but how is that any better? Do you use escrow? What about local BTC selling services?

Basically, I'm looking for the safest way to move higher-valued amounts of BTC to Fiat (and not get screwed by someone) in the event that I choose to do so.

Just trying to be prepared! Thanks.