Well, the best and safest way to be cheap relative to other portables is to not include fancy features. In other words, don't cheap out on important things (Voltage regulators, batteries, tools (depends), etc.) For every else, feel free to cheap out. For my PS2 handheld, I'm planning on using a 5" car backup camera I got off amazon for 20 bucks. While this is great, I'm very well aware that it won't be as nice as a 5" IPS screen. Another thing you can do to save money is to use TI regulators instead of the PMS. You'll lose features like pass through charging, but its cheaper. Think about what you want in your portable, and then plan out what parts you're going to get.
