Hi,
I am using the SpeedyBee F405 v4 stack and 1000 kv motors, and I was wondering what battery I should use and what remote id (a cheaper remote id) I should use?

The SpeedyBee F405 V4 FC can take up to 6S voltage (25.2V).

1000KV are very low powered motors. What type of UAV are you planning to build? Is it a quad or a wing, and what type?

The Remote ID module is going to depend on what type of quad/wing you are building.

I am building a quadcopter the frame is the parallax elev-8

OK, can see that you're building what is an old school type DIY drone...

https://learn.parallax.com/sites/default...-Guide.pdf

The Parallax ELEV8 assembly manual states to use a 3000 to 4400mAh 20C LiPo and recommends Parallax part number #752-00010 which is a 3S (11.1V) LiPo, so that is what the 1000KV motors which are part of the kit will be designed for. So I suggest you just go with that voltage LiPo which will be suited to the motors. You don't need to get the Parallax branded LiPo. Any 3S LiPo in that capacity range will do which has a C rating of 20 or higher. The SpeedyBee F405 V4 FC can take a voltage anywhere between 3S and 6S, so using a 3S LiPo with that flight controller will be fine.

For that type of drone it would probably be best to get a completely standalone broadcast Remote ID module that includes a built-in GPS module. I suggest having a read of the following articles to help you decide which one might be the most suitable for your particular drone:

• https://pilotinstitute.com/remote-id-modules
  
• https://www.thedronegirl.com/2023/11/06/...-id-module