That area is actually very well serviced by PT, as Buckley St and Millieara Rd are main routes, many buses cross that intersection ... if she had an unregistered myki she could travel unidentified, the short 1km walk to Buckley St would have her on a bus going straight to Essendon Station and from there she is 20 mins away from any vline train she wanted to hop on. If she had been planning to run off, stashing some cash, then heading somewhere on a bus or train would be pretty straightforward. Be interesting to know if CCTV at PT hubs was checked for that day. Rent a room in a large rural town for 100-150 a week or even less, $2k could get you a few months wiggle room to set yourself up a bit. I must admit I do find this hard to picture from what we've gleamed of their chosen (incongruent to income even) lifestyle. Perhaps more likely cloistered away by a lover than living hand to mouth.
The relationship between Sarah and her mother would certainly shed some light and we have read the interstate cousin says they are close. I have reason to believe they are the one and same who made the somewhat negative "million dollar question" comment on FB so I am guessing they are at least somewhat hostile to Borce and so perhaps less open to the idea Karen is involved in her own disappearance. I question the accuracy of an interstate cousin's impression of their relationship, people are often wearing their masks even at family events, and enmeshed or conflict laden relationships can still see people calling frequently and spending a lot of time together. Not saying this is their relationship, just that to me the cousin's impressions do not rule out, for me, her leaving her poor daughter in this limbo.
As for her body being found if she had committed suicide, surely Daniel O'Keefe gives us some pause there.
I have mentioned Lorrin earlier in this thread as well Pepper77, I think they have a lot in common. She was experiencing stress also, and had even younger children. For some reason she stopped her mail, and her last purchase of a water bottle always makes me wonder if she went somewhere to take too much medication. Borce tells us Karen went back upstairs, if he is innocent and being honest, this detail is interesting. His narrative is short but he starts her "leaving" with her going upstairs before coming back down and going through the garage. Did she retrieve something from upstairs? Medication, money, myki, hidden prepaid phone .... ? Or just the handbag and purse?