OK, seriously now, some questions:

Full basement? Or crawl space?

If its a crawl space, you might be able to put one end of a vacuum cleaner hose in your car's exhaust, and the other end in the crawl space to gas them. They may not go for other bait, but they can't just ignore carbon monoxide. If you do this, you probably want to stay somewhere else that night (take your pets too) and air out the house when you get back.

Apart from that, continuing with the mechanical traps, D-con type poison and even those sticky sheets is about all you can do. You've had some success already, so you know it works. You have to continue until you get them all.

I'd put the sticky sheets at all of the entrances and exits to your crawl space, and also all around any holes so the rat HAS to step on it if he uses the hole.

In spite of my nonsense above, there's probably only a few, and once you get them all and plug the holes, problem solved!


https://www.dropbox.com/sh/ey71h8ep047758h/AAC12jNM0Hz9Q8zsh5iDeqNHa?dl=0