I'm unaware of traditional numerology calculations for determining favorable times to sell ancestral property.

Determining calendar day numbers that resonate with the family name number may provide auspicious timing. (The family name is often referred to as the last name in Western society.)

Use the destiny number tool to obtain the family name number. The destiny number is the number obtained by adding the values of all the letters of the name and then reducing the result to a single digit. The calculator does all the calculations for you when you provide the family name.

With the family name destiny number at hand, you can determine which calendar days resonate with that number.

Here is a chart of resonating days for each of the 9 possible destiny numbers.

Destiny Number	Resonating Days
1	1  10  19  28
2	2  11  20  29
3	3  12  21  30
4	4  13  22  31
5	5  14  23
6	6  15  24
7	7  16  25
8	8  17  26
9	9  18  27