Aside from the standard BR/BA count and square footage, I always focus heavily on the listing pictures for any comps I pull in my area - finding a comp that's as close to your property's condition and finishes will give you the best apples-to-apples comparison possible.I also wanted to second @Tim Swierczek's input: nobody in Minnesota likes moving in the middle of winter.  

You may not get the first property you offer on because if it looks good to you, you will probably have competition so start offering on properties that fit into your personal investment philosophy and meet your minimum financial requirements. 

I'd go on ABnB and see what your competition is doing that you can copy.Maybe a Firepit out front (as long as it's not a fire hazard), maybe a cornhole set?

Assuming the Oakland rental market continues to remain stagnant/competitive with newer buildings going up, is property appreciation the only way to increasing wealth with my building?

The competition is fierce but I think you can still find great deals.

@Peter W.From my experience, a second-home investment strategy works best when you meet lender conditions like owner occupancy and rental restrictions.

Investors normally get there payments on time, most of the tenants stay for long periods of time because if they move it is a hassle for them, and since section 8 requires that the property stay in certain condition it will help keep the maintenance costs down. 

On market & negotiated price based on condition How did you finance this deal?

Here are thoughts on building strong vendor relationships:1.Timely Payments: Pay vendors promptly upon completion of work to maintain goodwill and encourage continued collaboration.2.Fair Pricing: Negotiate competitive rates without undercutting the value of their services.

I think you'll just generally have less competition, so your chances of landing a property are higher, but I'm not seeing any bargains due to seasonality like there used to be.