I'm applying UK visit visa application on behalf of my parents and my father is retired and currently his income is coming from a several lands lease, flats rent also he has some savings, my mom is his only dependent.
All payments are paid to my father by cash and most cases my father doesn't deposit any payments to his bank accounts. It's going to be extremely hard to show regular cash flow about these payments, however, he has all the property's documents to show he owns them.
Is it necessary to show proof of these above incomes if yes then how?