I think 3-4 days is the max I've had for vacancy that was the by choice so I could address a few things.

We have been trying to learn everything we can but we certainly don't want to make uneducated and poor investment choices. 

We are beginning to see a bit of a slow down with buyers in San Diego, this could be a great time to get back in the market depending on your goals and neighborhood of choice. 

@Javaughn HarknessExcellent choice.

We have 2 loan scenarios: FHA with 3% interest rate and 3.5%($17,000) down BUT we have to claim $150k of income on our tax returns for 2 years and pay IRS 70K (2 years worth) total in taxes because we are self employed. 2nd scenario: private lender offering 4.5% interest rate with 5% ($27,000) down 8 year interest only loan converting to fixed thereafterwhats the wise choice?

If you can’t agree on a price that you are happy with then your only choice is to cancel during your due diligence period.

You don't buy BRRRR's, you buy SFH that turn into BRRRR's, so I'm not sure what the real question/choice you have here is.

We have thought about finding a partner to invest,  but my wife is not fully convinced that a partner is a good choice because neither of us know how to get a contract for that type of thing written up and she doesn't want to be taken advantage of. 

@David Cozzi 3 ways people typically enter multifamily, your choice :Scale up slowly, learning on their own. duplex, quad, 10 unit, etc.Buy a Mentorship and network. 

Not sure how many units/property you want, but the near west side (West 117th down to West 25th area - extending south to I-480) has lots of older apartments (many just 4 or 8 units, some bigger) and is becoming a popular area again.