Is there a way to enter my transactions to take the place of "class"

[Floyd Cornell]

I have rental properties and with MS Money I enter transactions by category
(say utilities) and then by class (say B street).
I would love to use Gnucash and Linux, but I have not figured out how to be
able to make reports showing income and expenses for each property, and
reports showing income and expenses for each category. I would think this
must be a pretty common need, and I'm just not understanding it.

Also, I export my register to a csv file which is converted to Excel so my
accountant can use it to do my taxes.
Can Gnucash export in a format that can be opened by calc or excel?

Thanks
Floyd