<prompt> Human: I have 10k I want to invest in a fund and have already maxed out my 401k and IRA contributions so instead of it just sitting in my high yield savings I want to put it to work. Was thinking about dropping it all on the VFIAX sp 500 fund. Is this the best choice for my money? And if it is, how should I contribute? Should it be contributed in a few parts over time or lump sum? VFIAX has a lower exp. ratio compared to VFINX but requires a 10k minimum.  <response>: Best is to create an asset allocation plan across all accounts, and implement that, instead of looking at a single account in a vacuum. Best is to use admiral funds. Best it contribute all at once. 