Lets say that you earn 100k in business A and 10k in business B.Business A 401k does not allow non deductible contribution while business B 401k allow supplemental non deductible contributions.

This is just to supplement my retirement In my 401k and Roth IRAs.

What is your long term investing goals, to be in the trenches running your Reno’s and having a rule on everything, be laid back at the top and let the work trickle down, or just snatch up a couple properties to supplement your intended lifestyle.All these things take a factor into your decision.

I'm sure I need her to re-do or fix the notice form fixed or supplement it, and I'm tempted to ride over to the house and have her do it tonight but it's getting late.

If you speculate your local market will continue to appreciate well, using the rental income to supplement may be an option.

A long life friend and I have finally reached a point in our lives where each of us can contribute the same amount of capital towards investing in some rental properties to hopefully generate passive income and supplement our retirements later in  life.

(Some tenants in college towns try to supplement their college experience with sub leasing the floor..

It's always just been supplemental income, though. 

Books and podcasts are great supplemental material, but they cannot be a substitute for actually going out there are diving right in.

So now I'm posing this as a supplemental question to the original.