Hi @Adam Treboutat!! First and foremost, you have an unbelievable rate on that loan. Congrats to you for getting that. To add to that, to be in Marin County anywhere and look at 5.6% cap rate prior to accounting for your mortgage is spectacular.
Before I give you my 2 cents, let me give you the calculations that we do.
[Annual gross rent - mortgage - property taxes (insurance, maintenance, etc.)]/[cash in property + any capital expenses] This will more or less give you the rate of return on just your cash in the property. I think if you're going to compare apples to apples, it's necessary to determine what the rate of return is on the cash, not the overall property. If you were going to sell and move your money elsewhere, that's the math you'd be doing more or less.
If I were in your shoes and looking at that kind of mortgage rate, I would be inclined to figure out how to increase the revenue on the property. I'm the first proponent to say don't over renovate your property. You won't necessarily see a proper rate of return if you install marble countertops. However, I'm a believer that quartz/granite is more than sufficient to get you a quality price and tenant.
And although I would love to agree with @Soh Tanaka, you gotta know that there is no way you're picking up multiple SF properties with $700k especially not at the 1% rule. To add to the struggle, there are reports (and BP blog posts) that show that rents are actually decreasing in some of the more metropolitan areas as millennials become part of the next wave of suburbanization. Keep in mind that transactions are costly. Whether it's tenant turnover or property turnover, real estate agents and wholesalers get paid for that special skill set.
Hopefully this helps and don't hesitate to reach out if you have any other questions/concerns!!!