My husband's symptoms started with slurred speech and twitching in his biceps at about the same time. We have never been sure whether it was bulbar onset or not. He lost his speech at about the same time he lost the use of his limbs. He was diagnosed four years ago and is now paralyzed. He just recently lost the ability to swallow, which is causing a lot of trouble with mucus.
We also checked into the cost and difficulty caring for someone on a vent. With our insurance, we would have paid about $500/month for the actual equipment. The big expense is in the home health care. We would have paid thousands of dollars for 24 hr. care, which you need on a vent. My husband questioned whether 24 hr. care is really necessary, but we found out it is. Someone on a vent needs suctioning anywhere from 3-20 times a day and it can not wait or the patient will choke. If family members are available to take turns and be with you, it would be much cheaper. We were told that it is a little tricky to learn how to do at first, but it gets much easier with practice.
Because my husband was not sure of where his ALS started and which abilities he would be losing first, he waited until it progressed quite a bit before he decided about a vent. He wanted to see what his quality of life would be when his breathing became a problem. Because he can not eat, speak, or move, he has chosen not to go on a vent.