Should I bring a sleeping bag?

Only if you are strictly camping or staying in very remote areas. Most budget backpackers use hostels, which provide linens. A silk or cotton sleeping bag liner is a better, lighter alternative for questionable beds.

Do I really need a money belt?

No. They are uncomfortable and a dead giveaway that you are a tourist. Use a hidden pocket inside your bag or keep your cash/passport in a secure, zippered pocket in your pants.

Is it better to buy expensive gear?

Not for a first trip. Buy mid-range gear to see what you actually use. You can upgrade later once you understand your personal travel style.

Choosing the Right Gear for Budget Backpacking

Stick to a 40-liter backpack to avoid checked bag fees and keep your weight under 10 kilograms. Focus on versatility with your clothing and leave the 'just-in-case' items at home; you can buy almost anything you need on the road for cheaper than the cost of bringing it from home.

Select a carry-on size pack. Buy a 40L backpack with no wheels. It fits in every airline overhead bin, saving you $30-$60 per flight in baggage fees. Look for a clamshell opening rather than a top-loader so you can see all your gear without digging.
Adopt a modular packing system. Use packing cubes. Put all shirts in one, pants in another, and underwear in a third. This keeps your clothes compressed and organized, meaning you don't have to dump your entire bag on a hostel floor to find one sock.
Prioritize a 'wear-three-times' wardrobe. Bring enough clothes for 5 days and do laundry once a week. Choose fabrics like merino wool or synthetic blends that dry overnight. If you can't layer it or wear it to dinner, don't pack it.
Limit your electronics. Carry one universal power adapter with multiple USB ports. Don't bring a laptop if a phone or tablet will suffice for booking transport and checking maps.

Should I bring a sleeping bag?: Only if you are strictly camping or staying in very remote areas. Most budget backpackers use hostels, which provide linens. A silk or cotton sleeping bag liner is a better, lighter alternative for questionable beds.
Do I really need a money belt?: No. They are uncomfortable and a dead giveaway that you are a tourist. Use a hidden pocket inside your bag or keep your cash/passport in a secure, zippered pocket in your pants.
Is it better to buy expensive gear?: Not for a first trip. Buy mid-range gear to see what you actually use. You can upgrade later once you understand your personal travel style.