Wrong question.
The right question is which type of LN node you want/need to run.
Private or public ?
It's  big difference.
Read more:

bitcoin

What’s the cheapest laptop I could get to run a BTC and LN node?

satgoob

Wrong question.
The right question is which type of LN node you want/need to run. 
Private or public ?
It's  big difference.
Read more:
- https://darth-coin.github.io/nodes/lightning-node-maintenance-en.html
- https://darth-coin.github.io/nodes/private-ln-nodes-en.html
- https://darth-coin.github.io/nodes/recommendations-ln-node-operators-en.html
- https://darth-coin.github.io/nodes/managing-lightning-node-liquidity-en.html