So, should I continue to save and build up more capital to put down on a more expensive property, find something for less than 4-500, or pull some equity out of my primary and look for something with a higher entry price?

Are you sure your monthly asking price is accurate for the current time, accurate for a duplex in a duplex neighborhood, and accurate for this neighborhood.

Because of the seller's asking price.

You have a purchase and sale agreement with the seller, negotiate price, submit it to an escrow company and they do all of the work.

If these have the 2 position's to make up the puchase price, how can I use BiggerPocket's in finding the 2 lender's to satisfy each position to purchase the cash flowing property?

I'd say it's worth it if you have enough deals to justify the price.

You'll need to negotiate terms that work for both parties, including the purchase price, interest rate, and repayment schedule.

That is not a reason not to make changes, just something to put in the evaluation.

On top of the 'commonly used' investor filters like 2+ years back taxes, recently inherited, etc- I loved some additional possible/ unique filters like number of structures on a parcel, min/max land sq ft, initial purchase price, and ability to narrow down to very specific areas on a map.

I'm currently helping two clients find a starter house in Bergen County for the same price $500k-$640k Max.