What's a fair price for a Dell Inspiron i7?

Hey everyone, I'm looking to offload my old laptop, but I honestly have no clue what it's actually worth, so I figured I'd check in here...

Dell Inspiron i7, Intel Core i7 3632, 8GB RAM, Intel HD Graphics 4000 and Nvidia GT635M

Selling it without the disc, battery lasts about a minute if you even bother to unplug it, and yeah, it definitely shows some wear. I've had it for 6 years now...

How much is that

I don't want to clutter things up by starting a whole new thread, so I thought I'd just ask here: how much do you think I could get for this setup?

HP Pavilion DV6-6118sl 15.6
Intel I5 2 x 4
2x 4GB RAM
Kingston 240 GB SSD
Toshiba 640 GB HDD (swapped out the optical drive for this)
4x USB
1x HDMI
1x VGA
Battery life is roughly 30-60 minutes
The laptop has this little quirk where the screen occasionally goes black and everything freezes up—it’s totally random, too. It might happen once every few days, or sometimes even less frequently. I’m certainly no tech expert, but I figured someone who knows their stuff could probably figure out what's going on and fix it easily.

Thanks so much!