What to do about Water marks on furniture?

Equal parts of vinegar and olive oil. Rub with a soft cloth. I've also heard that mayonnaise works.

Toothpaste. Rub it on and then rub it off.

https://www.thespruce.com/remove-a-water-mark-from-wood-furniture-1976384

if the ring isn't too bad, toothpaste is a great trick. if it is deep, then you might try wet rags with a steam iron. don't be over zealous, and keep an eye on it as you progress. do be careful if you try this.

Make a paste of olive oil and salt. Let it set on the marks for an hour. Then wipe it up. The salt will pull out the moisture and the olive oil will replenish the wood. Best of luck to you.

Place a dry cloth over the mark. Iron set to medium heat and go over the cloth. White (not gel) toothpaste and a damp cloth. A dab of toothpaste on the cloth and gently rub in a circular motion.

Thanks I will let my neighbor know.

thanks