Dont go anywhere near webuyanycar, they always give stupidly low prices.
To get an idea of used car prices, check 2 guides, ie Parkers and WhatCar valuations, then look at what equivalent cars are up for on used car sites and ebay and it should be quite easy to work out what yours is worth doing these things, then you price it accordingly, it doesnt even matter if it hasnt got certain things really as long as its priced bearing that in mind, ie LOWER. Its not rocket science.
If you dont bother to do that because you love your car and think its worth more, then youre a fool, we may all love our cars, but we all know its not about that, its about what the market says theyre worth, end of. Price it too high and it ll just sit there until it rots away, or until someone ignores the price and looks at it anyway, then offers you what it IS actually worth . . . mind you you d probably turn them down.