All the conventional wisdom around what you should spend on housing seems to be around 25% of post tax income. This seems horrible to me as it doesn't control for windfalls, earnings growth, etc that a lot of us have.
To have say 10mm worth of homes, how should we think about if we can actually afford that?
My thinking is that the down-payment should be no more than 10% of net worth and that the mortgage + taxes + maintenance can be like 33% of a conservative estimate on post tax income over next 10 years as well as a conservative return on investments say 5-8%
So to afford 10mm in housing, you would need 20mm net worth for down payments and then say mortgage and everything is 50k/month or 600k a year you would expect to have income of 2mm a year over next 10 years as well.