This one is of particular interest many "gurus" repackage free info and sell it for a premium

Lots of folks doing whatever they can to bump their premium post up to get likes/attention, so their name gets the love on google search.

The redemption price is: The bid amount, Plus any taxes paid by the purchaser after the tax sale, Plus any special assessments on the property, Plus a 20% premium of the amount for the first year or fraction of a year which has elapsed since the date of sale and a 10% premium for each additional year or fraction of a year thereafter plus the sheriff and advertisement costs.

The premium you would have to pay for a lock is going to be like a whip.

Why I Love Student HousingRent Premium - Students will typically pay 40-50% more in rental income than market rate housing.

You're essentially paying a premium for a "turnkey" property, in my opinion, for this particular deal.  

Over the years because of California insurance regulation policies, companies like State Farm were unable to raise premiums fast enough in these areas to meet the current insurance costs. 

(It is overpriced and the Seller mistakenly believes an owner occupant will be willing to pay a premium price for it).

My lenders have all quoted between 7 and 8% which if you look at conventional owner occupant rates really the premium we pay on investment loans is dropping. 

You forgot the really really bad, Colorado is a premium bidding state and almost all tax sales will sell with a premium.