You should strive to invest 25% of your income if only to get used to not having that money so you can scale it back to 15% once you have kids.

So I’ve been a saver for as long as I can remember and in my younger years and have finally had a child in my 30s. Despite making a combined 120,000 a year with my wife, we purchased a 235,000 home with 20% down so our mortgage payment, taxes, and utilities comes out to be around 15% of our income, and now with daycare for one child that’s about 12% of our income and when we have a second child daycare will be another 12% of our income. If we continue to contribute 25% of our income towards retirement, that adds up to 70% of our income. Now, if we ever feel a little pinched, we can just scale back our retirement contributions to 15% I stead of 25%, but we are used to living on much less than we make (no other debts). Anyway, that’s an anecdotal example of why I think people should strive to save 25% of their income. Obviously the other life choice of buying a house much less than we can afford (I understand the struggle is real out there) but also driving our modest cars into the ground for as long as we can (Hyundai and Prius) contributes to our financial comfort.