The fee itself does not automatically go up because you know the area. Most one-off bird dog fees are set by the investor's standard rate, and a stranger handing you a check for the first time has no way to verify your local knowledge. The address looks the same to them regardless of who found it.
Where your knowledge actually changes the money is in two places.
First, lead quality. An investor paying $200 or $300 for a lead is really paying for the probability that it closes. A lead that comes with accurate context, vacancy status, condition notes, how long it has sat, what comparable sales look like on that specific block, is more likely to convert. Higher conversion means investors will keep coming back to you instead of the person who hands them a cold address. Repeat business from a reliable client is worth a lot more over time than a slightly higher one-time fee.
Second, negotiating position once you have a track record. After two or three leads close, you have evidence. That is when you can have a real conversation about a higher rate per lead, or even a percentage of the assignment fee (the profit an investor makes when they pass the contract to another buyer). A percentage deal on a $10,000 assignment is obviously better than $300 flat. That conversation is much easier once an investor has made money from your leads specifically.
The one thing worth knowing before you go further: some states require a real estate license to receive compensation for finding buyers or sellers. The rules vary and this is a legal question, so check with a real estate attorney in Tennessee before you sign any fee agreement.
What are the investors you're talking to actually buying in Whitehaven right now, buy-and-hold rentals or fix-and-flips? That changes which distress signals matter most in your notes.