Northwood, EBay i would suggest, colour seperated listings by weight is easiest. Unless you’ve got thousands of pieces to sell and the time to itemize everything Bricklink / Brickowl will be a drain, plus some stuff may sell immediately whilst others will sit in your store for years. EBay is not good for single lots though as postage makes the pieces silly expensive.
I think the problem with the dedicated selling platforms is you need to have a crtical mass of parts which means a buyer might find a lot of parts they want from you which covers postage.
db that’ll keep you busy for good few nights, I build fast and it took me a week to build. Biggest issue is where to store it and how to pick it up without it exploding.