Better Investment Strategy? (Better usage of money)

[Brett Fox]

I'm sure there is some type of formula for this but thought i'd post it here for some feedback. I am trying to determine which of the following 2 options gives me the better return on my investment. There's a good chance I'm leaving out some relevant information so please let me know if I forgot something relevant.

I have money in mutual funds that has given me a 2.1875% return a year.

I am in the process of purchasing a condo that will be used as a rental.

I am trying to determine whether the money in my mutual funds account would be better utilized as a higher down payment or remaining in my mutual fund account.

With 25% down payment the property is going to produce a cash flow of $424 a month. The more money I put down obviously the higher the cash flow will be.

How do I determine how to optimally use my funds? Hopefully that was understandable lol. Thanks for the help.