OK... I decided to actually do a calculation to see....
I am using real return from my Vanguard account for the past 10 years by month...
My thinking.... I have $120,000 to pay off a mortgage or invest that money... if I pay off the mortgage then I have nothing left to invest but also no mortgage to pay... sot that is basically zero...
Now, I can also invest that money... use money from my account to pay the monthly mtg payments... there is no need to figure out P&I because at the end of the loan I will have put in $120,000 of equity under both options...
So, $120,000 loan, interest rate of 3.125 for 15 years (close to what I have)..
Now the surprising finding to me...
If I started 10 years ago, Jun 2008, invested my $120,000 and started to pay off the mortgage.... I would be DOWN just about $23,000..... I would have $22,621 invested but a remaining mortgage of $45,663.... It would not have been a good decision to hold onto my money and invest it...
So, I said let me do one starting in Jan 2010.... close to when I actually got the mortgage... well, I would be DOWN about $18,000..... investment balance of $40,896 and a mortgage of $58,938....
It seems strange to me, but the math I am doing shows it is a losing game.. the problem is taking out that monthly payment... it is very rare that you make enough for the full payment, only 3 times in 10 years... so the remaining invested balance drops on the bad months and the good months never bring you back up....
So, what am I doing wrong? Or have I been thinking about this wrong the whole time?
To add... just did one from Jun 12 as there were a number of up months... so I thought THAT would do it... NOT... still have $12K less in the account than the mortgage....