- It's not for sale.
- Oh, come on. That's a ... Are we taking bits off this one, right? This one's a scrapper, is it?
After "Come on", he starts a sentence with "That's a" but then changes his mind and starts a new sentence. "Are we taking bits off this one?" means "Are we going to use this car for scrap parts?" That's confirmed by his next sentence.
Remember - if you don't use correct capitalisation, punctuation and spacing, anything you write will be incorrect.