So, I'm moving to manchester next week and need some advice where to stay and not to stay. I'll need to buy a car asap as well. Any advice on good car dealers, property agents, and which areas are nice to live in?

I know Manchester quite well. Salford is a quite rough area so is Moss Side, Alexandra Park estate and Withenshaw. Hulme estate has been demolished and rebuilt but is still rough. Ancoats to the east of the city centre is Ok, and so are some of the southern suburbs like Sale and Stockport are fine places to live.

I live in Didsbury which is a great area. Loads of bars and restaurants, handy for the motorway and 10 minutes drive into town. It's a bit pricey, but it's the best part of town. If you're on a good wage and like the party lifestyle, choose to live in the Northern Quarter in the centre of town. There is some other decently priced city centre living, such as near Picadilly.
Other areas I'd recommend are: Chorlton (bohemian), Sale (towny), Whalley Range (leafy).
Don't know much about North Manchester, so maybe someone else can help you there.
Avoid: Mosside (asbo hell), Ashton (boring), Salford (rough), Rusholme (good for curries), Fallowfield (students and burglars)