Okay so how carspecial.com and carspecials.com they're two diff businesses, should carspecial.com try and make a new name for theirselves or hope that customers dont get confused? What would you do in this situation? I am in the current senerio right now.
If I owned two identical domain names (one is plural and the other singular) I would probably use the one that's plural.
It depends on how much organic traffic you get. If a lot, then no, I wouldn't change it if I were you. If it's a brand new domain name and you want to swap it for another brand new domain name then it makes no difference.
I will suggest you to keep carespecials and apply redirect on carspecial if you haven't different content on this website. If you have different content then you should keep it but it means double expense for you.
It relies upon on how much natural visitors you get. If a lot, then no, I would not change it out if I were you. If it's a product new sector address and you want to exchange it for another product new sector address then it does not matter.