When I bought my car used, the previous owner gave me a key fob for some awful aftermarket anti theft and keyless entry system, and I immediately wanted to get rid of it.

Plus, who doesn't want the fun button on a remote to roll down the rear window

I searched around to see how I could tell if my car had the factory keyless entry option, and I found some threads that helped, but had a few comments from people who were confused, but I found a pretty easy way to find for sure what exactly my 4Runner came with.

This link: Vehicle Specification | Toyota Owners

It seems like the obvious way to find out, but it seems that plenty of people don't think about it.

Simply type in your VIN, which you can find on the dash (and a few other places), all the way in the front corner where the windshield ends.

If you are just looking for keyless entry, search the page (by pressing control+f for most browsers) for "KEYLESS ENTRY"

There are also some interesting bits of information I found, such as the order date, date of first use, and my exact paint color.