If you are still using stock AV cables with your old consoles, they can be modified to look a lot better! I've listed the more popular RGB and HDMI console mods below, but you can contact me if you are looking for one that isn't listed. I've done most of the installs detailed on https://retrorgb.com. Prices do not include shipping, send a PM for any questions.
Here's some pre-modded consoles I have for sale:
PSX SCPH-5500 system with X-station mod (JP system, works on US power)
Power supply recapped, Low-profile SD card mount/extension installed. X-station firmware has been updated to the latest version. $250, comes with Dualshock 2 controller, AV and power cables, and OEM memory card
Pictures: https://imgur.com/a/Op98Yvw
Red Q5 IPS-modded Gameboy Color system with Pixel Mode and OSD menu. Systems have been recapped. Touch sensors cycle between brightness settings and GB color palettes, and the OSD menu can adjust the screen position and turn the battery indicator and pixel mode on and off. $130
Pictures: https://imgur.com/a/t11A4MS
Red GBA with funnyplaying IPS v2 screen and a Retro-six custom case with a soft, grippy texture. The inside of the battery compartment and battery cover is unpainted white plastic. System has been recapped, has a power cleaner circuit installed to reduce audio noise, and has an improved power switch: $130
Pictures: https://imgur.com/a/8URqAz9