Is it compulsory that the dca amount must be a fixed amount? If yes that means investing can be burdensome and can make investors to use part of the money that they should have use to solve their expenses to completely their routing fixed amount of money for DCA at whenever their expenses becomes more larger than the previous week or month, for those that have a stable source of income probably a permanent job having a fixed amount for DCA can help to become more discipline in fact it can even become automated in a considerable way that it will not have a negative influence in sorting out their other needs, but for those that doesn't have a stable source of income maintaining a fixed amount for DCA will definitely become more difficult because of irregularities in their income flow, that is to say DCA amount shouldn't or must not be compulsorily a fixed amount for flexibility.
It is not compulsory that that the DCA amount must be fixed amount,an investor can decide to be using a fixed percentage of his discretionary income let says %70 to be doing DCA or more and this fixed percentage is not a fixed amount it varies with the investors discretionary income.An investor can decide to increase or decrease his DCA amount as per his level of discretion.however as long as DCA is concerned the investor must maintain buying bitcoin at regular intervals and holding for a longer time.An investor DCA strategies should be able to suit there income flow and long term goals.
Trying to balance everything is actually the main idea. That's why it's always advisable that before you venture into Bitcoin investment, you should be able to have a job job not necessarily a well paying job but atleast one on which you can atleast draft out something from and put into buying Bitcoin and still not be affected by it and that's why DCA method comes in handy. The amount of money you used in buying Bitcoin should always be your discretionary income and it's shouldn't always be fixed amount because trying to make it a fixed amount is not bad also but it can make you to commit error especially at times when everything doesn't line up but persistent and continuity is the key because the whole point of DCA method is to grow your portfolio steadily for a long period without being affected and if you continue buying no matter how small at the end you will see the results for your self.
You know what they say "ROME WASN'T BUILT IN A DAY' also " SLOW AND STEADY WINS THE RACE".
Although there are other effective method also when investing in Bitcoin like the lump sum buying method too and many others but the DCA method is always preferable if your hands aren't that strong in terms of cash flow.