The “net” in the statement seems to refer to cash flow, but it could also be NOI (net operating income).

Doing a basic calculation of the property:

List price of $305k, Gross Income of $600*12*9=64,800. Assumed expenses around 33% of the gross income = 21,384.

I get a cash flow of about $25k. NOI = $43k.

So it seems that the $27k is about cash flow. But you’d probably better ask the owner about the numbers (always a good idea when investigating investment properties).