I use (and have setup many a developer) a T450+ Lenovo off eBay. Wipe it and put Linux on it, install an m2 SSD, 20 Gb of RAM, and get the bigger battery pack.

I use (and have setup many a developer) a T450+ Lenovo off eBay. Wipe it and put Linux on it, install an m2 SSD, 20 Gb of RAM, and get the bigger battery pack. Total cost is around $900 to $1100. It works better, with longer battery life, and I like the 14 inch display personally