% of net worth in primary residence?

Buy the apartment outright.
Enjoy living for (COLA/inflation adjusted) $700/mo for the rest of your life

Depends on what your definition of 'financially independent' is.

"Unstable income" and "financially independent" don't usually go in the same sentence, because true financial independence means that you have total income (earned or unearned, but typically unearned) from some source that is guaranteed, and guaranteed to equal or exceed all your expenses, for life. At that level, a primary residence is just another semi-liquid asset in a portfolio of investments.

If you have to work for some portion of income, you aren't truly 'financially independent'.

Some of the more stringent co-ops (who are more likely to have people who are fully, or close to 'financially independent') will expect that your total *liquid* assets be between 2.5 and 4x the purchase price of the unit. Use that as a guide, and think carefully about what you mean by 'financially independent'.

5% max.

I love this question. A case could be made for 0%, that you're better off renting for your primary residence, and owning real estate as investment property only. (I do believe every portfolio should have some real estate in it somewhere, for diversification if nothing else.)

It depends a lot on what kind of lifestyle you're seeking, how many different places you want to call home each year, for instance.

I also agree with Aaron completely. Independently wealthy to me means it doesn't matter whether you work or not, you're secure for life. So the unstable income part is irrelevant except of course to certain co-op boards.

I personally am cold on co-ops for people who are affluent enough to purchase a condo, because one of the joys of having money is flexibility, and all co-ops that are worth investing in are always restrictive. But if you have to live in a pre war on Central Park's east side, well, then, your options are limited.

percentages are meaningless here.
when you are first buying your goal should be buying with a good downpayment leaving aside living expenses for one year(adjust the recipe based on taste). However based on the premise, don't over-buy(choose a smaller/less expensive home ) and don't buy a second home

The older you get, the less of your net worht should be tied up in real estate. Hopefully your home becomes a smaller and smaller percentage of your net-worth.

Real estate should be looked upon as an investment to beat the inflation. Prospects of long term capital appreciation beyond inflation in real estate is entirely not clear and depends on your entry/exit from the investent . For long term perspective ( 10-20 Years), pension funds allocate 10-20% of the portfolio in real assets. If you take the same philosophy, you can invest the same proportion of your capital ( keep in mind that the mortgage can create a levergae effect of 2X3 times, which depending on your risk appetite, should be avoided).

I would go for safety first. Either pick a place with low carrying costs where you would be happy to live in (worst case scenario that gives you a cheap "rent"). Or go for a very liquid type of apt that you could sell in a few days (so that worst case scenario is you loose 10%).
Most people who buy real estate make a mortgage and actually invest more than 100% of their net worth. If you are rich, it should be part of your portfolio like bonds, stocks, gold, etc...

>The older you get, the less of your net worht should be tied up in real estate. Hopefully your home becomes a smaller and smaller percentage of your net-worth.

First, start selling off the extra bedroom, then the extra bathroom, next start getting rid of stuff in your closets so you can sell those

% really depends on the absolute magnitude of the nest egg. $1 mil vs. $5 mil is a lot.

I think of it this way... nest egg is an endowment... take 4% a year as your "income". Now calculate what you can rent or buy with that (with a 20% down payment).

It is impossible to answer your question as no one has a clue what any of that means.

"unstable income & career" but have "saved up enough to be financially independent"