£40-£50 is about right. Take some decent pictures:
Front - picture off.
Front - picture on.
Front - medium close-up of manufacturer logo
Rear - wide angle (all of the set's back panel plus power cord neatly coiled)
Rear - close-up(s) of connector sockets
Rear - close-up (and in sharp focus!) of product label showing model number
Front - remote control
Rear - remote control with battery cover in place
Rear - close up remote control batteey compartment with battery cover and batteries removed to show its clean and corrosion-free
It hardly needs saying that a clean looking TV, dust free, complete, and shown in full working order will sell faster and at a better price than some crappy-looking listing with bad images.
Your pluses are the brand; it's not a cheap make as bought from ASDA/TESCO/Argos. It's complete and working without issues. And it's clean
These are the things anyone buying a cheap used TV will be looking at.
List it as a 'HD-Ready Samsung 43" TV - full working order. Complete with remote"
Advertise at £50. Be prepared to haggle a little. If selling on Facebook, don't agree to hold for someone who says they'll collect. Say it's first come first served. Don't agree to deliver unless it is paid for in full first. This isn't home shopping with pay-on-delivery where someone says they want it and then changes their mind after you've made the trip. Stuff sells quick on FB, but you have to watch out for the tyre kickers and time-wasters.