Under two hundred dollars there is no single best microphone for rap vocals, but there is a best microphone for your room and your delivery. The choice comes down to one question: is your recording space treated or not?
If your room is untreated, buy a dynamic microphone
Dynamic microphones have a tighter pickup pattern and lower sensitivity, so they hear you and largely ignore the walls, the air conditioner, and the traffic outside. They also handle loud, aggressive delivery without the harsh distortion condensers produce when you push them. The trade-off is that they need more clean gain from your interface, and they capture less high-end detail, which you can add back with a gentle high-shelf while mixing.
If your room is treated, a condenser gives you more detail
Large-diaphragm condensers pick up breath, texture, and the top end that makes melodic hooks sit forward in a mix. In a treated space that detail is an advantage. In an untreated space it is a liability, because the same sensitivity that captures your ad-libs captures the reflections off your closet door.
What actually matters in this price range
Self-noise, off-axis rejection, and how the microphone responds when you get close to it. Marketing frequency charts rarely predict how a vocal sits in a hip-hop mix. Cardioid rejection and proximity effect do. A microphone with strong low-end lift up close can make a light voice sound bigger, but it also turns plosives into thuds if you do not use a pop filter and stay slightly off-axis.
Do not forget the chain around it
A cheap interface with a noisy preamp undoes a good microphone, especially with dynamics that need forty to sixty decibels of gain. If you already own an interface with weak preamps, an inline gain booster is a cheaper fix than a new microphone. A boom arm, a shock mount, and a pop filter also matter more than most upgrades: mechanical noise and plosives are the two problems that actually ruin takes.
USB or XLR?
USB microphones are convenient and fine for demos, voice memos, and streaming. XLR is the better long-term buy because the microphone, the preamp, and the converter are separate purchases you can upgrade independently. If you plan to record guests, XLR is the only sensible answer.
A sane buying order
Get the dynamic microphone, spend the leftover money on a pop filter and a boom arm, and put whatever remains toward blankets or panels behind your recording position. Then leave the gear alone for six months and record fifty songs. The improvement in those fifty songs will come from your delivery and your mixing, not from the microphone you almost bought instead.
Reader question we get constantly
“Will a better microphone make me sound like the records I like?” No. Those records were tracked by engineers in tuned rooms and mixed by people who do nothing else. What a good microphone in this price range buys you is the absence of problems: no hiss, no room, no clipping. That is enough to make a release-quality song.