When responding to ads and speaking with the seller, is it good business practice to let the person know up front that I am a wholesaler with a list of investors?

Also, if a listing or ad is actually a investor or another wholesaler listing the property and has the property under contract is it good practice to continue a deal with them?

I was told today that it's not good practice to with hold my investors name when speaking with the seller, but I don't feel comfortable giving out other people's information. Should I keep my investors info to myself?

I know that I get quite annoyed when I'm on the phone for 5 minutes before the person says they're a wholesaler.

As I look at it, efficiency in qualification is the name of the game.