Best place to sell an old working TV...

I have a 43 inch plasma screen TV.
In really good nick. Yes it's 10 years old but ice never had any issues.
Im upgrading because I no longer want virgin media which allowed me to connect Netflix and prime...
Now they wanna charge me extortionate prices it's got to go.
Long term its better I sell this and get a smart tv...

So any good advice would really help.