you don’t even have to been wealthy to be able to accumulate Bitcoin all what is just required is to have a discretionary funds to invest with boom you’re good to go it doesn’t have to be on a daily basis, depending on when you’ve a discretionary funds to continue accumulating bitcoin gradually and to hodl for a longer term period.
Instead of going with the method of investing today and still wait until you have a discretionary fund, why don't you hold on until you get a good source of income even if it is not stable, because investing today and still wait until you get a discretionary income is as if we are just joking with our bitcoin investment.
I see that you don't understand the meaning of discretionary income and that's why you feel that one discretionary income is not important before you can invest into bitcoin. Whether you have a stable source of income or not, you need to have a discretionary income from you stable source of income or unstable source of income before you can start up your bitcoin invest. Discretionary income is the extra money that is left, after you must have taken care of your monthly expenses and basic needs. It's that extra funds that you need to invest with. Some people use this extra cash to do whatever they want but it's wise to put yours into bitcoin weekly/monthly overtime.
However, an investor needs to wait for his next discretionary income in other for him to continue his bitcoin accumulation if he has already used the one that he has at that moment.