Drivers License Renewal Bali/car registration

The legal position is until the end of your visa, but that often varies.
I've seen licences issued to KITAS holders assuming they're tourists,  and to KITAP holders for one year instead of until the expiry of the immigration document (Very common).

As for cars held by a KITAS/KITAP holder, I don't know of a limit but you have to pay a higher rate of tax if you own more than one car, and too many might well bring too much interest from the wrong people who might well assume you're running a business.

From my experience a SIM is valid for a year regardless when your legal visa expires. 5 year SIMs are not unheard of in East Java for expats and that might be the case as well in Bali.

For ownership of vehicles as Fred said there are tax implications when register more than vehicle in the name.

I managed 5 years on my last one - no idea how, but I did.