If you don't have someplace to go, you really have no need of a bugout bag. A BOB is supposed to hold three days of supplies so you can get from your home to a more secure location that you have stocked with everything you need to be self sustaining. If you don't have that location then you need an emergency kit to get you through a week to 3 week emergency until help arrives. For emergencies you should have at least 1 gallon of water per person per day. Warm clothes and several pairs of socks and underwear, work boots, gloves, some filter masks, for each person. You need four ready to eat meals a day for each person and a snack along with eating impliments. You should have any necessary medicines, dry-wipes and first aid that you can use. You should have a packet of your important papers and recent pictures of all family members. You may or may not want personal protection but if you don't have it then whatever you have will likely be taken from you. Some other items are a knife, ax, a means to start a fire, and some form of personal shelter. Around your home you should be able to turn off the gas, electrical and water in case there are ruptures. Turn these off before you leave.
I know you said you are on a budget and that limits what you can buy but it doesn't limit what you can re-purpose or recycle to use in an emergency. Think outside the box and do what you can, with what you have and where you are.
Best wishes - you know we all started out where you are right now. Keep the faith.