Is there a way to take out a loan on your Bitcoin like how Ethereum can be used as a CDP in the MakerDAO to get DAI? I wanted to sell some BTC to pay some bills, but I also didn't want to lose out on the Bitcoin rise in the inevitable future. Ethereum has the ability to be used as a CDP (“collateralized debt position”) to get the stablecoin DAI which you can cash out at coinbase, but still own the Ether you put up for the loan. As long as you pay back the loan, you can get the eth back.  Is there a method of doing this with Bitcoin?
The closest method of doing this is using an exchange that provides margin trading. The only issue I have with it is that you need to trust your BTC with the exchange. One can recreate what the makerdao has with better rates too, but with a more centralized approach. 

Say you wanted to cash out $1000 USD worth of BTC (ex. 0.1 btc @ 10k btc price), but you also don't want to sell it because you see the price might be higher in the long term. What you can do is the following:


Deposit 0.2 btc ($2000) onto an exchange that provides margin.
Sell the 0.2 btc for USD. Now you have $2000 in your account. 
Send $1000 to your coinbase or however you want it in and cash out to your bank account. Now you have $1000 USD in your bank. 
The remaining $1000 USD that is on the exchange. Open a margin buy position for 0.2 btc. 
When the price of BTC doubles from the price you sold at, you close the position. Now you have back your 0.2 BTC minus the fees. 


The liquidation price of your margin position will be usually 50% of the price you sold at. Say its 10k, if you were to get liquidated, BTC would need to drop to 5K. 

Bottom line, your basically taking a loan out with your BTC as long as the price doesn't drop by 50% from the current price. Also to note, not your keys not your coins risk if the exchange exit scams or freezes your account.