Usage. Is this to be a min dev machine? ("99%") if so look into 3 things

- port replicator: some way to plug in ergonomic keyboard, mouse + external screen

- power & recharge (at a power point? or are you mobile all the time?)

- Operating system availability: (are you happy with using Windows, OSX or do you want to install inux/nix?)

- Warranty (can you extend it?)

For me the sweet spot is a ThinkPad T61. Reliable, durable, has necessary accessories and you can get Linux pre-installed (by third parties)