Your first question is easy to answer: Any government lien seems to stick, so you need to research whether those exist.

http://www.biggerpockets.com/government-owned-property.html

The government takes the money out of the poor tax payers pockets (reverse Robin Hood Syndrome?)

Interest income is taxed at regular income tax rates, so you can make the case for paying the AFR (applicable federal rate).

Anybody working in Seattle and making less than $80K are moving to Tacoma-Puyallup-Auburn- Federal Way etc. - Demand is crazy and vacancy is super low.

Obviously I find this confusing; the discounted home that is non TK has older systems (roof, HVAC, Federal Pacific Panels) and is priced 12k under ours is a pass and the homes with all those items updated, new and TK is to expensive.  

(Government declared no more subsidies for flood insurance and actuarial rates will apply).

Many of the secondary market buyers of loans, or guarantors, like Fannie Mae and Freddie Mac are Government sponsored entities, whose purpose is to promote home ownership.

Regardless of state law (most of which require lots of disclosure), as a real estate agent or broker, do you disclose what you plan to do with the property after you purchase from a non bank or government owned property.  

@George Lambrinos@Steve BabiakAt Judicial Tax Sales, the overages go to the liens including judgments, mortgages, Federal Tax liens, state liens, etc in order of precedence.