<prompt> Human: If large investment loans have about a 4 apr, and the average stock market fund return is anywhere around 8, is there a catch to just investing in a fund like the S and P 500? ie take out 100k to put in SP 500, and pay off apr with average investment returns? If this is doable, can the investment returns be set up to automatically pay off the apr costs?  <response>: is there a catch to just investing in a fund like the S and P 500? Can you continue to make the loan payments even if the market tanks and takes years to recover?If yes, then no, theres no problem. If no, then yes, theres a large problem. If this is doable, can the investment returns be set up to automatically pay off the apr costs?Probably, though youd have to consider what happens if the SP 500 has a -30 return that year. 