san francisco property to be auctioned at $ 2.5 m starting price .
it was made available on april 4 after police evicted a hoarder and removed her mother 's mummified corpse , which was at least five years old .
body is believed to be that of anna ragin , who lived with daughter carolyn .
police said house was full of black widows , rats , feces , bottles of urine .
authorities struggled to open the door of the home because of the debris .
carolyn is being mentally assessed .