For trading, I prefer a workstation-grade laptop + docking station + additional monitor. Low power consumption and portable if you need it. Off-lease means the machines were previously used by a company that had a lease agreement with a finance company that purchased the assets from a PC manufacturer such as Dell, Lenovo, HP etc.
A trading computer need not be "fast" nor have "super low latency". High performance computers are mostly necessary for gaming. Not so for trading computers.
or as elite traders we could all have a back up at the ready and not have to rely on a company to bring one to us but then again you get the latest and greatest but it would not have your platforms and setups unlike a back up computer.
What to consider when buying desktop computers. Do you trade in and out of the markets daily, then flat at days end? Is it dedicated to trading only? Will it be running 24x6 with automated strategies? Do you need more than 4 cores for running optimizations on 4 years of tick data. Trust me you will need as many cores as you can afford. I have quite a few cores and some optimizations take well over 5 hours. It all really depends on how you will be using the machine.
Yes, but some of us are from a IT / Software background. If your options spreadsheet gets corrupted, I am sure you wouldn't even dream of having a third party fix it. Same with some of us. We can't really think why we need someone else to swap out ram / hdd / busted power supply etc. A trip to Microcenter or Fry's and all is well
Traders should have backup... both software and hardware. If your system breaks down on your end and you can't have it back up in short order, it's YOUR fault. "Shit happens." You know that. Be prepared for it!