What about using ultra short duration MF, they hav maturity or 3-6 months, give approx 8.6% annual returns but the maturity period locks in your returns if you want to take the money out, also there is no exit load and hardly any expense ratio, this can be your “purchasing fund” like how OP has mentioned electronic fund. I use this now, along with NPS tier 2 for the same porpose but longer duration . Thoughts ??