That could depend on the specific activity you were involved in and the type and severity of seizures that you have. There could be roles you could possibly play, even if it was only in the offices and not on the boats. You would need to contact your local coastguard to find out what medical requirements you have to meet to get into the coastguard.
If it is active, in treatment, or untreatable, then yes; it will disqualify you from service.
No.
Not at all. You're there to do a job.
A loan default wouldn't disqualify you from joining the National Guard.
A medical condition such as that would disqualify you for enlistment, let alone becoming a sniper.
A felony does not automatically disqualify you from joining the army.
The coastguard saved that man's life.
Netherlands Coastguard was created in 1987.
Her Majesty's Coastguard was created in 1829.
I would expect that epilepsy would disqualify you from working as a police officer. However there are many support roles that could be done with such a medical condition. Requirements vary from department to department, so you would have to inquire with the unit you are interested in.
There are a lot of things that would disqualify you, such as blindness, epilepsy, angina, bipolar, many heart conditions, a reliance on illegal drugs and many other conditions.
Depends on the situation, it's a case-by-case basis. Usually yes but there are exceptions. You could get a waiver.