I got a relative who wanted to go into the deal and he paid the back payments and the repairs.

Management is impossible to select until you have picked and vetted a firm- while it is an operating expense, you're likely going to pay from GOI...so assume closer to 12% NOIYour vacancy is pretty low, but it's all relative here...I would at least set aside 1-2 months gross rent for an unexpected turnoverIf you can insure a 4-unit property for $150/mo. you have an awesome agentAssuming 50% of your income will go to OpEX is pointless.

The text of the contract as it relates to obtaining financing reads: (b) This Contract is contingent upon Buyer obtaining approval of a conventional FHA VA or other ______________ (describe) loan within _______ (if left blank, then 30) days after Effective Date (“Loan Approval Period”) for (CHECK ONE): fixed, adjustable, fixed or adjustable rate in the Loan Amount (See Paragraph 2(c)), at an initial interest rate not to exceed _______ % (if left blank, then prevailing rate based upon Buyer’s creditworthiness), and for a term of _______(if left blank, then 30) years (“Financing”).

(They should be willing to spend an hour or two hashing this out with a therapist since they are asking you to make a longterm LIFE CHANGING commitment for their benefit.)

Concrete will wick moisture  through it even if a basement is relatively dry.

CA benefits from a glorious past with tech industry and entertainment industry to name a few, that were built before CA became effectively a one party system; and this "People's Republic" unfortunately also "occupies" more than half of our beautiful West Coast with prime real estate.

If you have specific questions, you can post them here to benefit the forum.

another related question - is home insurance cost different between condos and single family?

Let me know if you have any Orlando related questions, I'd be happy to help. 

Especially before you invest in LA, read the rent control policies, especially those that relate to how you can have a tenant move out and how much you MUST pay them to move, based on how long they stayed there, etc.