And, of course, also, if you feel that you do not have enough, you can continue to DCA.. even if it is only $10 per week... though for fee purposes, it may be better to let your amount build up to something like $80 or $100 and then buy once you reach certain thresholds of value.
It that's the issue probably better to keep coins on the exchange until you have enough to make the (artificially high) fees worthwhile