Tefillah stands in the highest places of the world [concealed from man's sight].
Tefillah is also concealed because we recite Shemonah Esrei silently and discreetly. Therefore, נכסיו refers to tefillah. Chazal are saying, נכסיו שיתקיימו הרוצה, if a person wants his tefillos to be answered, ;אדר בהן יטע he should pray on Rosh Chodesh Adar. "His prayers will go up...and everything will become chesed and rachamim."
It is good to say Tehillim on Rosh Chodesh Adar. Reb Sariyah Dibletzky zt'l (Davar Nechmad) writes, "Reb Eliyahu Cohen and Reb Chaim Abulafiah zt'l heard from Reb Chaim Vital's students that one...should recite the entire Tehillim on Rosh Chodesh Adar. This will fix his neshamah. There are other secrets too [why it is good to say the entire Tehillim on rosh chodesh Adar]. It is proper that those who fear Hashem should gather to make this tikkun."
For those who cannot say the entire Tehillim on Rosh Chodesh Adar, it would be good for them to say some chapters of Tehillim. Because the rule regarding spiritual matters is that if you can't do everything, do as much as possible.
The Kedushas Levi (Shekalim טעם ה"ד) writes that each month represents another tribe, another shevet. Adar corresponds to the tribe of Yosef. This is the reason there are sometimes two Adars (as it is this year). It is because Yosef branched into two shevatim, Menasheh and Efraim.
Yosef is renowned for his kedushah, which means Adar is an ideal time for attaining kedushah. This brings us to our next topic:
Kedushah
