The Moneyist: ‘I would hate to see their efforts evaporate’: How do I help my adult sons manage their finances — without being an interfering parent?

Dear Moneyist, 

My two sons are in their 30s and both well educated and have rewarding jobs. They save well and spend within their means, for which I’m very grateful. They each want to buy a home, for which saving is an almost Sisyphean effort, as one lives in Boston and the other in San Francisco — both of which are great places for real-estate investment but terrible for first-time home buyers.

Both…