I would like to spend half a day getting a glimpse of what it's really like to live in Higuey. I am not interested in a sugar or tobacco plantation tour or beach visit. Can anybody recommend a tour?

If you are scoping it out for a move or long term visit I'd think a ''Tour by Locals" would be your best bet, not a predominantly 'sightseeing' tour.

Something like one of these:
https://www.musement.com/us/punta-ca...gessen-404129/
https://drlocals.com/tour/dominican-day-in-the-life/

To see what a place is really like, I would just walk the streets on my own. Get a good map, put yourself in a central location, find the municipal market, grocery stores, church, school, etc.

Unless you've lived in the Caribbean before a half-day visit to Higuey isn't going to give you much insight to what it might be like to actually live there. You really need to spend an extended time (suggest 3 to 6 months - the longer the better) living like a local. Do not stay in a hotel or at a resort but rather stay in a rental condo or house that approximates the type of accommodations you'd be in if you lived there full time. Do everyday chores like grocery shopping, paying utility bills, banking, normal household and yard work, cooking, laundry - in short try to live like a local. Spend time commuting between your residence and the places you shop, find out what it's like to drive and park your car 'downtown", check out housing costs, prices of goods and services you'll need when living there, check out what's available for leisure time activities, read the local newspapers to get a feel for the local political climate and whether or not crime is a significant issue. It's the only way to determine if living there meets your expectations and fits your lifestyle.

100% to the post above! You can't get a feel for living in a place on a single vacation trip. If you are really interested what it really feels like to live there you don't want to take a "tour". That will not tell you what you need to know.