This is a super question. Everyone's finances and career goals are different. I really like that you are weighing all your options. One reason to consider the 5 year option is to cut down on the tuition costs. I would look at your budget for the 5 year option vs. the budget for a 4 year undergrad + 2-3 MBA (it will be more). I would also project out what you plan to do after school and whether you need to work during school. Work experience is valuable and some schools will let you do cooperative learning or consult for companies trying to solve operational issues through capstone courses. Business school is very intense and you might like this emersion. Once you get out you will have more time and seed capital potentially (because school cost less) to start a business or buy a house.
Employee tuition assistance programs are super and you are very lucky to live at a time where there are so many fabulous online and executive MBA programs. Companies will generally make you focus on specific areas that benefit the business and there are some expectations about paying back the tuition and maintaining good grades. Take some time to look at these corporate options as well, cost out MBA programs compared to reimbursement (this is a multiyear commitment) and weigh the costs and the benefit of traditional and executive programs. Look at the networks/alumni associations you will be able to tap into in each. Look at the industry or field that matches your interest and have multiple plans for achieving your goal.
MBAs are lifetime learners and it is very likely that you will have core business knowledge as well as a major field: MIS, HR, Accounting, Marketing, Security, Finance, Operations Research, etc. This combined knowledge and expertise is what makes you valuable. There are some fabulous opportunities to use an MBA in a STEM field (Science, Technology, Engineering, and Math). These fields pay more in general, are super in demand, and will literally rewrite the economy as we know it). Some of these specialties will require additional certifications most likely and continuous learning - but that is very good and makes you more valuable.
Since most professionals have multiple careers over their lifetimes this means that you will be going to school or learning online or in the classroom throughout your career. I am very excited for you. Attaining your MBA is an incredible journey, lots of hard work, and super rewarding. Remember to work closely with your classmates because everyone does better by working together. Whenever you feel like you aren't getting something, chances are there are 10 other classmates who don't get it either. Keep going, be positive, and find mentors and friends to help you on your journey.
This field will definitely take you places since MBAs work all over the world in all industries and sectors. Consider internships as well as volunteering to develop your network and find your way. There are non-profits that need and work with MBAs as well and many corporate programs encourage volunteerism. By helping others you will learn more about yourself and meet so many amazing people in both business and other areas.
You are definitely on the right track!