My recommendation: don't give access to any security deposits or personal property until someone gives you a court order appointing that person as the personal representative of the estate. 

If there are more than these sons, and she left no instructions, and the courts appoint an executor someone could claim you rifled your tenants belongings.   

I plan on setting up an appointment with you so we can speak further on how Re/max can help me with my property management.

I could hire anyone I wanted as long as they were FHA certified.2.Purchase agreement reflecting 95% of the appraised value3.HUD-1 statement4.Letters of appointment showing my seller was appointed as the executrix of the estate.5.Letter from seller stating their intention was to do the short sale for 95% of the appraised value6.Letter of Authorization for note holder to speak to me on behalf of the estate.7.Proof of funds.So while I waited on probate to clear, I hired an appraiser to go get the property appraised.

As far as time goes, I would say if you're doing it yourself, it could very well take 40 hours plus building lists, researching, taking calls, making calls, going on appointments, etc. 

Also anything that would help with scheduling the subcontractors, The quotes they give me and appointments

Now that being said if they have a lot of equity or motivation I'd schedule an appointment and just cross my fingers.

Comparing 'like' homes via home sales is inaccurate, as homes prepped for sale are usually repaired to better condition for selling.Appraisal board members are appointed/nominated by the taxing entities, kind of a conflict if you ask me.  

It needs to be done by an appointed valuation firm from your bank, they will give you a list of companies to contact.

I've had many estates end up with no equity when unsecured creditors like Medi-Cal pop up.If you want to just buy the asset, someone else needs to be appointed PR or at least complete the summary probate (or similar process in your locale for a small, informal estate).If you are only interested in making a profit rather than owning the asset, there are many, many exotic and sophisticated plays than can be executed.