It takes a lot of money to control that type of portfolio outright. 

ValuePenguin is a good source for the relative cost of insurance by state.Operational Costs - Costs like property taxes, insurance cost, state income taxes, regulatory costs (ex: time and cost to evict), inspections, rent control, etc., have a tremendous impact on your return.

My best guess is that rent control will be coming in the next 2-3 years.

I've been told that due to "Force Majuere".Force majeure is a common clause in contracts which essentially frees both parties from liability or obligation when an extraordinary event or circumstance beyond the control of the parties, such as a war, strike, riot, crime, epidemic or sudden legal changes prevents one or both parties from fulfilling their obligations under the contract.

@Kevin Sobilo your response is fantastic.

Previous owners had done a fantastic job of taking care of the property with a solid long term tenant.

Previous tenants had seen some but we got pest control to treat it and it wasn't a major issue.

Looks like a fantastic Investment!

California Civil Code section 1671 controls the amount of late fees you can charge. 

House hacking a 4-plex is a fantastic way to start your investing journey.