There are dozens of ways, though, to buy investment property without any downpayment. However, make sure that either the property will cash flow, or that you (or partners) can absorb the monthly losses. In many parts of the country, it's difficult to make properties cash flow even with substantial downpayments.
Among the ways to purchase a property with no downpayment:
Get another investor, one with cash. Purchase the property together (equity share, and/or in an LLC or land trust). They put up the cash; you presumably manage it or handle the other aspects of the transaction. You share in the proceeds.
Persuade the condo's owner to provide financing. If he/she doesn't need all the money out right away, the owner can be the "bank." It can be structured as a land contract or deed for contract.
Lease-purchase the property.
Use an Illinois-style land trust, and use a technique called a NEHTrust. You have the owner put the property into his/her land trust. You become an investor beneficiary of the trust. You find a resident beneficiary to rent the unit--typically for the amount of the mortgage. Now there are three owners of the trust--the seller, you, and the resident beneficiary. The resident beneficiary provides the up-front money and the monthly payment. At some point in the future (usually a couple of years), the property is brought out of the trust, the resident beneficiary refinances the property, and you and the original owner receive some of the proceeds.
Subject-To. This works with distressed properties. The owner transfers the deed to you, but remains responsible to the lender for the mortgage. You may pay the seller a token amount. You pay the mortgage. And at some point you refinance, thus putting a mortgage in your name.
Those are just a few ways to buy an investment property with no downpayment. However, again, since you don't have any available cash, you really have to make sure that either the investment will have a positive cash flow or that you have a way to handle the negative.
You should consult with an accountant and a lawyer to make sure you're safe and protected.
Hope that helps.