What are you prepping for? What are you prepping against?
Everyone wants to talk about guns and ammo, but the reality is that you should probably be looking at provisioning yourself to be able to stay home for 60 days without going outside. Lots of problems can be solved by locking the doors and leaving the blinds closed.
Food and water are the immediate staples. I like keeping a month or two of freeze-dried type meals on hand because they take up very little space and are portable. If you're MIL/LE, you can get the Mountain House pro-deal and save some cash. Something most people don't think about is that you can buy a case or two of Ramen and some Mountain House #10 cans and repackage meals with a food saver to quite easily get a 30-60 day supply of food on hand for less than $300. If you camp and hike or hunt you now have a ready-made pool of meals for your trips. If you eat canned foods it makes sense to just buy one extra can each time you replenish. Let's say you eat some canned chili and you know you're going to get more, just buy two cans instead of one. As soon as you use one, buy two more if it's a common item. That's the easiest way to build food storage. Buy what you eat and eat what you buy.
Water is a bit trickier in an apartment. I have a big ass house with a huge pantry, so I have no problem storing water. When I lived in an apartment, I would buy cases of bottled water for general consumption and store them in a closet. No one thinks twice when they see cases of water bottles, and it's an easy way to keep 50'ish gallons on hand without a bunch of drama. The next best thing to get are some of those bathtub bags used for hurricanes. You can fill them up in your apartment while you still have water if you think water might be getting scarce. Buy some plain Clorox bleach and a bottle with a dropper. It's super easy to remember that two drops in a quart of clean water will disinfect it. Four drops in a quart of murky water. I have filters and other stuff on hand, but Clorox Bleach is the best thing to keep around for long-term use. Every six months, I pour the entire bottle of bleach into the upper tank of the toilet and scrub it out to keep that water source viable as well. Each prep should make sense; I've got a purification method that can also clean and sanitize.
If you can have a gas grill or stove get an extra bottle of propane for it. If not, find your best backpacking option and make sure you know how to use it and have fuel laid in for the stove.
Keep your vehicle tank filled up. Most problems in the USA can be solved by driving one tank of gas away from the problem. Keeping a few months of cash on hand is key to being able to drive away. Don't forget that cash is king.
You guys can get back to swords and guns now.