Thank you both! The Perfomix Super Grip spray must be what was still lodged somewhere in my memory. Now to FIND it locally without having to buy over the internet and pay shipping that doubles the cost. Glad to know about the non-slip materials too. I think the spray will be more 'do-able' since I don't fancy sewing strips or corners on four area rugs. (His sink, my sink, shower and tub rugs.) The floor heat is great, but replacing four rugs every year isn't -- especially when 'no treds' is the only thing wrong with them. I did get use out of two 'sliders' in the car over the winter to spare the carpeting.

Great ideas here; I knew I could count on you! Some of the ideas are out of our price range, which is probably under $100. Chispa, yes, I'm worried about duct tape residue, but wonder if there are solvents that might remove it if we go that route. Lily'smom, just removing the carpeting and seeing what is under it might be the best option if the LL approves. Then vinyl or paint the subfloor, like you suggest. lpink, I think that's a great idea, but not sure our next place will have a need for mats, so we kind need to do something cheap and temporary. nosoccermom, I think the plastic wrap would be too hard to seam so it's liquid proof, but the carpet saver looks very interesting and affordable. The garage mats are too much $$, but would work great, I suspect. laughablemoment, those planks might work if we pull up the carpet, so will look at them, too. pattycakes, thanks. I did look online at the HD pads, so will visit in person to see if they are suitable to use alone. kirkhall, I'll have to look and see what forms of vinyl are available within our budget. Maybe I'll swing by Habitat and see if they have any remnants for cheap we could try out! Thanks again for all the great ideas. Something here will work, I'm sure!

All felt if you have no concern about the rug slipping. (like when the rug is under furniture) A felt and rubber combo if you do. This site has a ton of explanation. https://www.rugpadusa.com/collections/for-hardwood-floors

I have a shag rug in my living room with heavy furniture. However, I would recommend the same pad. Ru9padu5a dotcom (hope you can translate those #'s to letters). I chose the thickest pad with a rubber back for hardwood. I wanted to enhance the cushy-ness of the long shag. Superior Lock 7/16"