BP has two great books (I'm the author, so perhaps I'm biased :) ) that delves into gory detail on how to estimate and how to analyze deals:http://www.biggerpockets.com/flippingbook

.  :-)  But you linked to an article that I've read 100 times over the last 25 - 30 years written by different authors in different publications that have all claimed the same thing.  

I would use a legal authority to get rid of the owner/tenet.  

That law was passed in 1980 by Congress, no less.

You also want to get a "release of information authorization" and a limited power of attorney from the sellers.

I hope this helps.86.752 Foreclosure by advertisement and sale.A trustee may not foreclose a trust deed by advertisement and sale in the manner provided in ORS 86.740 to 86.755 unless:(1) The trust deed, any assignments of the trust deed by the trustee or the beneficiary and any appointment of a successor trustee are recorded in the mortgage records in the counties in which the property described in the deed is situated;(2) There is a default by the grantor or other person that owes an obligation, the performance of which is secured by the trust deed, or by the grantor's or other person's successors in interest with respect to a provision in the deed that authorizes sale in the event of default of the provision;(3) The trustee or beneficiary has filed for record in the county clerk's office in each county where the trust property, or some part of the trust property, is situated, a notice of default containing the information required by ORS 86.745 and containing the trustee's or beneficiary's election to sell the property to satisfy the obligation;(4) The beneficiary has filed for recording in the official records of the county or counties in which the property that is subject to the residential trust deed is located:(a) A certificate of compliance that a service provider issued to the beneficiary under section 5, chapter 304, Oregon Laws 2013 (Enrolled Senate Bill 558), that is valid and unexpired at the time the notice of default is recorded; or(b) A copy of the affidavit with which the beneficiary claimed, under section 2 (1)(b), chapter 304, Oregon Laws 2013 (Enrolled Senate Bill 558), an exemption that has not expired;(5) The beneficiary has complied with the provisions of ORS 86.748;(6) The grantor has not complied with the terms of any foreclosure avoidance measure upon which the beneficiary and the grantor have agreed; and(7) An action has not been commenced to recover the debt or any part of the debt then remaining secured by the trust deed, or, if an action has been commenced, the action has been dismissed, except that:(a) Subject to ORS 86.010 and the procedural requirements of ORCP 79 and 80, an action may be commenced to appoint a receiver or to obtain a temporary restraining order during foreclosure of a trust deed by advertisement and sale, except that a receiver may not be appointed with respect to a single-family residence that the grantor, the grantor's spouse or the grantor's minor or dependent child occupies as a principal residence.

Wisconsin is a Marital Property State, All Assets and Debts are both spouses, regardless of the name they are in, for example, I have Sole Member LLC's but my wife has 50% ownership even though she is not named anywhere, likewise her 401k is half mine as well, the little debt we have is also the responsibility of both parties. as a mater of fact, if you apply for credit in WI, there is a Required authorization of the spouse. 

I think I need to signup to 'Plus' or 'PRO' in order to be authorized to do this in the marketplace.

First of all, most bp responders have less authority than that of a government entity, yes, some have real life experience, but there are those who respond when they don't know the law and only heard stories about it but try to contribute as if like they know the law themselves.

@Brian Garlington I agree with @Daniel Gonzalez, while getting Section 8 tenants can have it's benefits, I found out first hand that even though rent control doesn't apply to Section 8, Oakland Housing Authority says that Measure EE part of Oakland rent control applies, which basically means you can not get rid of a Section 8 tenant unless they fail to pay rent.