I've read the Wiki but not sure about some things.

If I already have the products in my store and I just want to update prices and stock levels but not change anything else, what all fields are required to be used?

Item #, Price, quantity, if I just import those three fields, since the item number already exists on the site, will they be found and updated, but leave all other info as is?

Some-one mentioned I think that if the description field was empty it may delete the description from the item, what about if that field just does not exist?

I read that I can Delete items in bulk by using 9 in the status field. So 0 is inactive, 1 is active, and 9 will delete?
Is that correct?

What if I do not use a status field in the import? Will all the items remain as I have them already set, and ZC just set the status based on stock levels?

I have about 2,000 items available, but only want to deal with about 500 for now. The problem I have though is when I get a CVS from supplier I can choose what fields it contains, but ALL products will be included.

I'm trying to figure the best way to deal with with only 500 of 2,000 items.