Now that you mention it, giving it/selling it to a family member would be a good idea.
The main thing for the Vita is how cheap you can get it, if there are enough games you are interested in playing to justify a purchase, and if you will play it enough to justify a purchase. I got a used Vita maybe around half a year ago for about 100 dollars. It was like new with just a few scratches from being dropped but otherwise it was in great condition. It was a steal, and I've only bought one game... the rest are from PS+.
Remote play is pretty crappy for PS3, very few games support it, but apparently all PS4 games support remote play, so that would be a pretty great feature.
Since you have a PS4 you probably won't be using it much, so I would think it would be a good idea to sell it or give it away.
Been away for a bit, but sneaking back in.
Gaming on: PS4, PC, 3DS. Got a Switch! Mainly to play Smash
