Is there any type of paperwork required (i.e. registering my business license in the Inland Empire since it's a different county) in order to start collecting rental income? 

A local attorney can tell you if it's worth chasing the seller and don't forget, anytime you sue you pay, then only if you win, you get to try to collect. :) 

Part of me wants to sell, collect the profits and begin that way.

I know some section 8 landlords who don't worry about the collection part from the tenant, they go into it thinking they'll never collect it.

You will not have to pay the penalty nor taxes, but you will not be able to collect/spend the cash flow.  

If you are wholesaling, you need to let the buyer know that there is a lease-back involved in the transaction as they will be collecting the rent from the seller usually at closing.  

It's a collection of the best flipping info from the site.Oh - and be sure to set up some Keyword Alerts- especially for "Miami" so you'll be notified when people mention it here in the forums.Thanks again for introducing yourself!

A quick googling shows that you're supposed to collect Transient Occupancy Tax, although they may not enforce it much.  

@Roy N. have you ever collected on your "fine" or ever been successful in an eviction for smoking?

In this case, you would continue to collect rent, but they would have a set option price that they could exercise at some future point.