The HP EliteBook 735 G6 Notebook PC I recommended is not difficult. It's a cover, a connector and some torx screws. It's also more geared toward corporate use, not consumer. Your call. I can't recommend a prebuilt desktop, since I haven't owned one in a couple decades. I've always built those myself and used hand picked parts.What I learned today: many consumer laptops no longer have an easily (if at all) replaceable battery.
Made me start considering an Intel NUC or a traditional desktop.