Since you don't know if they were growing table grapes or wine grapes, I would start first looking at the table grapes suitable for home growing and if none of those pan out, look at some of the white wine grapes. You are in zone 7, but the article on zone 8 grapes includes zone 7 on most. Here are other articles that should help:
https://www.gardeningknowhow.com/edible/fruits/grapes/growing-grapevines.htm
https://www.gardeningknowhow.com/edible/fruits/grapes/different-types-of-grapes.htm
https://www.gardeningknowhow.com/garden-how-to/gardening-by-zone/zone-8/zone-8-grape-varieties.htm
This year, massive grapevine produced a lot of thick, green, healthy leaves, but no fruit. Just learned (from this site), the larger old wood should have been pruned aggressively. Only the smaller, newer branches were cut. Hopefully I can save life of vine and bear grapes next year. Who will know exactly how to professionally handle and rectify this situation. ****This vine has previously produced abundant big, sweet bunches for years. HELP!!!
As I see it, there are 3 options. One is to learn to do it yourself; 2 is to call a local winery for recommendations or employees seeking extra work; 3. call your local Extension Office for advice. (Search.Extension.org for finding your local office) Of course, there are lots of online videos! I found a comprehensive article that covers routine as well as rejuvenation/restoration pruning: https://catalog.extension.oregonstate.edu/sites/catalog/files/project/pdf/ec1639.pdf
You can propagate grapevines by rooting cuttings. Here is how:
https://www.gardeningknowhow.com/edible/fruits/grapes/rooting-grapevines-tips.htm
grape plants are large but berries small but plentiful
There are many, many issues that can cause these symptoms. I will include some links to some articles that will get you started in figuring out what is going on with your grapes: https://www.gardeningknowhow.com/edible/fruits/grapes/how-to-get-grapes-on-vines.htm
https://www.gardeningknowhow.com/edible/fruits/grapes/treating-grapevine-problems.htm
https://www.gardeningknowhow.com/edible/fruits/grapes/preventing-pierces-disease.htm
https://www.gardeningknowhow.com/edible/fruits/grapes/treating-grapevine-problems.htm
I have this very thick skinned white grape. I don't remember where I bought it and it was never labeled by variety.
This article should help:
https://www.gardeningknowhow.com/edible/fruits/grapes/thick-skinned-grapes.htm
We have a very nice green grapevine that has grown to finally produce grapes in our yard. However, we put grass in front of it and it's branching all over. We bought a big A-frame to plant the vine underneath so it can grown up and around the tall A-frame and possibly provide shade underneath for a swing. We just need to know WHEN we can transplant this - already read how and what to have ready, including the hole but hubby says NOW - in the Fall. It's gone dead...leaves shriveled, grapes gone.
This article should help:
https://www.gardeningknowhow.com/edible/fruits/grapes/rooting-grapevines-tips.htm
when is the best time to cut shoots from grape vines, how much to cut and what to do with cuttings
This article will lay out, exactly, what to do and expect: https://www.gardeningknowhow.com/edible/fruits/grapes/rooting-grapevines-tips.htm
This collection of articles will give you all of the information that you could need on grapes: https://www.gardeningknowhow.com/category/edible/fruits/grapes