You don't need expensive gear — here's what actually fixes a bedroom studio

Skip the foam. I know it's everywhere on Amazon. Foam attenuates 2 kHz and up — your real problems live at 200–500 Hz, and foam does nothing for them. You'll just have a slightly duller but equally problematic room. What $300 actually buys you, in priority order: 1. Two 4-inch thick mineral wool / rockwool panels behind the mix position. ~$120 DIY. 2. Two more at the first reflection points (mirror trick — sit in the mix position, have a friend slide a mirror along the side wall, mark where you can see the speaker). 3. A heavy moving blanket on a stand behind the singer for tracking. $25 from any hardware store. That's it. That's the whole list. Bass traps in corners are the next paycheck. This genuinely closes 70% of the gap between a bedroom and a treated room. People who buy $2k monitors before doing this never hear what their monitors are capable of.