Now this is very realitve,
First a page that generates $30 per day for someone will not generate the same amount if it changes ownership.
The first owner knew very well the content that his followers liked while the new one have to make a lot of tests. But on the other hand, if the new owner is good at content creation can even double or triple the income per day
$5k for a page like this is very high in my opinion, bcs Facebook is very unpredictable.
Maybe smth around 3months of earnings would be a better price offer. So $30/day = $900/ month x 3 = $2700