You are very fortunate that there is an account designated for your college costs. It sounds like there’s probably between $225-250k in there, which is such an amazing gift. Depending on how the account is set up (i.e. if you’re listed on the account or as a beneficiary) then it may need to be included in any applications for financial aid. If so, it might be unlikely that you would receive any need-based aid. Perhaps @kelsmom might be able to provide additional insight?
If you do not qualify for additional need-based aid, how do you propose to pay for the 4th year at $80k? College students can take out up to $27k in loans over the entirety of their undergraduate career. That still leaves you short more than $50k.
Additionally, did you speak with your family about whether they would be willing to have your educational fund be used for law school as well as college? Using the same “for instance” as before, if you went to a college that was $35k/year, then you would not only have all of your college paid for without loans (which is really the position you want to be in when you graduate from college, if possible), you would also have almost enough money for a year at an elite law school.
I am not an expert on post-grad years, so others will undoubtedly have better insight for you on that. But I do have a few thoughts, regardless. Where is the money going to come from for your PG year? If it comes out of your college education fund, that leaves less money for college. Would a good enough performance change your reaches into matches? Highly unlikely. Would it make a difference in your “match” schools? Possibly. Would I do a PG year for any of those reasons? No. The circumstance where I might see a PG year being helpful is if you’re working on your executive functioning skills and you and the professionals around you think you need another year of practice under closer supervision than is likely to happen at a college.
Personally, I would visit some college campuses (small, medium, large, and rural/suburban/urban) if you haven’t to see if you really do want a mid-size to large urban campus. I would also dig in on the websites of some of the schools of interest and look for things that make you excited and that horrify you, as those are things to be paying attention to when you’re looking at any college.
Most regulars on these threads recommend starting the college search by looking for schools where you are extremely likely to be accepted, that your family can afford without loans, and that you would be happy to attend, no matter what one’s stats. For some people, those are the hardest schools to find. Once you find those schools, then you can start looking for more selective ones to add on. But there are some great options at the schools I listed above, and as you can see from the institutions of where the Harvard Law students came from, you can make it to elite law schools from just about any school in the country.