Do you really want to go thru all the work of repair, cleaning, selling? You’ve done so much all ready.

When you say “old”, how old? Pre 1840, mirrors were made of mercury, before the danger of mercury was known.

abc.news:

• Don't buy antiques that contain mercury. If there's any doubt, have the seller verify that the item is mercury-free.
• If you have mercury-containing antiques in your home: Inspect each item thoroughly for cracks or leaks; replace or remove mercury-containing components if possible, but do not attempt to drain or replace the mercury.
• Mercury is a hazardous waste. Contact your local or state health or environmental department for advice on cleaning up or disposing of mercury.
• Ensure antiques with mercury are kept out of reach of children and that children are educated about the dangers of mercury.
• When handling mercury-containing items: Move slowly; support the item with padding; don't turn the item horizontal; keep barometers at a 45-degree angle when moving.

It’s just stuff in the end. How does your boyfriend feel about the remaining items?
You have a busy life already. Maybe your boyfriend can take on the responsibility of finding the value, if any, and disposing of it. Or use our method of disposing in the garbage weekly, bit by bit.

Since your life is busy, posting on sales sites would be time consuming. You might want to contact H&L Resale in Brockway or Now & Then resale in Luthersburg and see if they are willing to make an offer for them.

Antique mirrors without the frames have little value.
as for the dangers of a mercury/tin amalgum mirror backing, experts say that even a museum full of these old mirrors pose little danger. Some seem to over state the dangers of mercury....I have a mouth full of it....as do many others.

It’s not breathing mercury that’s the danger, it is if you cut yourself with a broken piece.

Do not suggest that mercury is not dangerous to you and the environment, Linda. That statement is very irresponsible and more, on your part.

• Mercury is a naturally occurring element that is found in air, water and soil.
• Exposure to mercury – even small amounts – may cause serious health problems, and is a threat to the development of the child in utero and early in life.
• Mercury may have toxic effects on the nervous, digestive and immune systems, and on lungs, kidneys, skin and eyes.
• Mercury is considered by WHO as one of the top ten chemicals or groups of chemicals of major public health concern.
• People are mainly exposed to methylmercury, an organic compound, when they eat fish and shellfish that contain the compound.
• Methylmercury is very different to ethylmercury. Ethylmercury is used as a preservative in some vaccines and does not pose a health risk.

It wouldn't be worth either the time nor the money to do anything to the mirrors. And I certainly wouldn't store them anymore. You might get $5-10 for them on FB marketplace, and that's a big maybe. They really have no value.

The mercury on the back of a very old mirror is of no concern, mainly because a mirror that age is so rare and secondly because the mix of tin and mercury is not a chemical compound and the actual mercury has evaporated many years ago leaving a mostly transparent mirror. I said nothing about mercury in shellfish.

In reality, the major source of mercury in our world is the mining and burning of fossil fuels. The mercury emitted settles into the ocean where it is stored in the bodies of large predator fish.

As I said, please don't be a fearmonger about mirrors that may possibly be 100 years old, when mercury has not been used on mirrors for about 180 years.

The OP said vintage, that could mean anywhere from 30 yrs to 100 yrs. To immediately jump to mercury poisoning is hyperbole. I seriously doubt they have mirrors from 1840 sitting under a tarp in their backyard, (that's when they stopped using mercury in mirrors)