I tried to hold back but speculation escapes me ..
it is not a raspberry-proof theory but it fascinates me:
Bella works (or worked) for the detective agency that will have to watch over the three heirs.
this would explain the apparent madness of having left home and work to assist her sister, now her work is there.
and that would also explain her schizophrenic attitude towards Elaine and MC, she wants them to collect their share and share it with her for different reasons (love and affection)
the doubt, the Jolly remains Jolina, an accomplice / colleague of Bella? or the third heir in Bella's web? I would say the first, for now Jolina has manipulated aspiring detective Jenna and her Scooby Doo very well
who watches the watchers? nobody
p.s.
Maviarab forgive me ...