@Steve Miller I am not an expert in Southern California but in San Jose where we see similar cap rates or lower in some cases where there is potential increase of the the renal income. Based on my experience having 50K or 5% down is going to be very hard unless you are willing to live in one of the units and get a FHA loan or seller financing.
The commercial loan interest here is closer to 5% from what I see here locally. Also for a 4 unit you will not need commercial loan. You need commercial for 5 or more units. So for residential you can get a loan for 4.5% but this is again with higher down.
For doing value add projects like you are planning you need more capital or partners with capital.
@Dan C. I know you had good intentions when you did your analysis and posted but your costs and analysis is wrong. One easy example is the property tax. The property tax is different in every state and even every city so don't generalize this. The property taxes in california are closer to 1.25% and the insurance cost as 1% of property is totally weird. for high cost areas where land is more expensive than the building. What I have seen here is 50 to 40 per unit per month. So for all 4 units you will have 200 per month.
The Vacancy also is totally dependent on the area in the area and can not be generalized.
I am not saying this is a good deal or you should do it. But please put real numbers and do the calculations.