I'll offer you $200 in BTC, and if I am able to get more than $1000 out (via powering down and exchange to poloniex), then I will split the difference of the remainder that I can get out in (as measured in BTC value I get out).

So you retain some upside if the price rises, you get some immediately liquidity out and protect yourself against total collapse of the price.

I have a 3 year reputation in crypto, see my introduceyourself post, so I would not reneg on the terms since it would disrupt my reputation which is very valuable to me.