Bismillah ArRahman ArRaheem
Wa-Alaykum As Salaam
1. If the man has children from that or another wife, the wife gets 1/8th of the estate, and the remaining part will be inherited by his other heirs. A wife does not inherit anything from the land of a house or a garden or a farm, or from any other land, nor does she inherit from the proceeds of such lands. See https://www.sistani.org/english/book/48/2387/ for further details.
Note every brother gets double the share of a sister. https://www.sistani.org/english/book/48/2385/ for further information.
So if $100 is to be distributed here in this example where the late father leaves a wife, three sons and one daughter, then
1. Wife = 1/8 = $12.5
2. Brothers will get 1/4 each = $25
3. Sister will get 1/8 = $12.5
4. TOTAL $100
2. If the intention of the father was that these properties remained under his own ownership and the sons did not have the properties at their disposal or discretion, rather the father had that discretion over the properties, then the properties continue to be counted as his own and are to be distributed as if they were under his own name.
3. The business is part of the deceased estate and must be included when calculating inheritance.
And Allah Knows best.