PMJI at the end of the line but for a repeater to be useful for you would you not have to find a location in your complex where the reception is good and locate the repeater there? Is that possible? If not then this from the second link John B gave would seem to apply:
<< How does a WiFi repeater work? Simple really when we think about it. It just takes in the WiFi signal from a remote radio device and then blasts it out locally. However, there are a few problems with this.
First of all, very often, radio devices fail to repeat if the make/models differ.
Secondly, it is essential for the repeater to get a good, reliable and stable signal from the radio first device. And if this fails to happen, then it ends up repeating rubbish or even worse, just slows the system down with repeated resend messages. >>
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