It's likely they aren't including all expenses including property management, taxes, insurance, mortgage payment, and capex/vacancy/repairs holdback. 

One of our local Milwaukee REIA groups offers a-la-carte coaching.

So if you can find a parcel that doesn't seem to have multiple fatal flaws, or at least you think you can add value to fixing/figuring out their constraints, then I would do that and then just flip on the MLS, especially if you are able to let it "season" a bit, which the title companies in California require anyway...they won't insure a flip of a tax parcel until some time has passed.

The dreamy master bedroom is spacious, offering a large walk-in closet and a master bath you have How did you find this deal and how did you negotiate it?

Meanwhile, while you wait for an uncontrollable event like appreciation, you are losing $1,000 +monthly if you have 100% occupancy on a LTR at $2k per month.( prop tax, insurance , mortgage)Cut your loses.

When you can't decide, make the offer.

Some of these properties are offered at a fraction of the market value which is one of the reasons investors are incentivized to buy.

Also, for anyone based in Philly, I've heard from one contractor that quotes of 20-30k were common a few years ago, but due to recent rule changes, contractors need to maintain excavation licenses/ insurances to do any dig out work and that cost is getting passed to customers.

My wife and I had a “corporate meeting” and we made them and offer and ended up purchasing the property for $1K over our offer price at auction.

Buyers expect Sellers to cower in the corner at their amazing low offers as if they are doing the seller a favor.