Base price for VCR Xbox is now $90 and with bonus trade in if you get PUR PRO would net you $125
With others have said, it will be harder to sell currently with all the deals going on with the Xbox One S and with Xbox One X coming in out in like 2-3 months. An advantage of trading it in over selling is it is quick and easy. Don't have to worry about shipping it/meeting someone for pickup and any other "work" related to selling it.
It is best to use it during deals like B2G1, Black Friday, or some type of amazing deal that does not involve MSRP.
There is another option where you can use this credit to make even more credit by buying and trading in between stores, but that involves doing some homework and time to figure out if it is work it for you.
Last possibly thing is if you are leaning towards digital content, you could always buy Xbox curreny/LIve from from.