This can be a slippery slope. I was in the health insurance business but, alas, have been retired 12 years and things may have changed. COBRA will be available to you if your present company has 20 employees. Many states have programs similar to COBRA that help employees of companies with fewer than 20 employees to retain their coverage for a time. You will be limited to 18 months continuance if you terminate your employment. It is true that you will pay 102% of your employers cost. However, your employers cost may be pretty high depending on the age, makeup, claim history etc of the group. After you use up the 18 month extension, you can convert to an individual plan but the conversion policy will probably have limited benefits and will be costly. My advice would be to carefully look into your options so you don't put yourself and family into a "crack". Unfortunally, this is a problem for anyone with chronic health issues.
If you move and go with a large company, you may be able to forego the above hassle. Most large company plans will be "guarateed issue" with no or limited pre-existing condition clauses. However, to be safe, don't let your current coverage lapse until you know how and when the new coverage will pick you up.