First of all, as you say, pulling turfgrass is a PIA, because it forms mats of sod. Time consuming and obnoxious.

How big is the area? Could you once again turn it over by hand, using a fork or spade, burying the sod on the bottom? Or, would that be too much work due to the size.

Another way to go -- roundup or a similar herbicide with short duration. The reason your grass came back is because its probably a cool season grass that sprouted from seeds. It's also possible your first application of herbicide didn't give total kill, and some survived to regrow - two applications spread a few weeks apart should get the survivors of the first round. I know a lot of people are against Roundup, but it does have its uses. One advantage is that it appears not to have long-term residual effect in the soil.

Another option, maybe - cover it all over with black plastic -- that should kill off anything under there in about 2-3 weeks.

And no, bleach doesn't kill plants for the most part. It may burn the tops, but it won't kill them long-term.

I also tried boiling water, which similarly seems to have done absolutely nothing to harm the grass.

One of the weeds I sprayed with bleach is looking a mite peaked. But the grass couldn't be greener. Its ironic, I guess. Most people want a lawn. But I have a 10x20 foot space, partially paved. If I have grass, I have to mow, water, weed. A moss lawn would be ideal, but getting from here to there seems to be the sticking point right now.

The herbicide has gone through multiple applications. But its about time to start the garden, and I really want things in it not to die. Plus I was considering some in ground stuff. So a seasonal ground kill is not what I am looking for, right as I want to start growing things. Plus I have to vacate my house for a day or two, cause the fumes cause major headaches for me directly after spraying.

Between the three, nothing will get through - and you can just them fight it out over who owns what territory.

Those might be good alternatives to the moss ground cover that was our goal.

But I struggle to believe that they can choke out grass which in just a few(dark rainy cold) months has already headed up a good foot high and has surprising density out in the center.

And, with all three, you can just pull up a clump, divide it, and plop it down elsewhere to fill in spots.

I would try that. After you have it tilled, put down a thick layer of newspapers and put a mulch over it all.

Or if you can't afford the rental, try the newspapers and mulch right over top of the grass.

I will not vouch that this is 100% effective, since I have done it for 2 years now in an area with creeping myrtle, and I still have some coming up, but maybe with grass it will work better. At least it is totally safe for the environment.

With a plethora of fist to head size rock. Digging it by hand was a royal pain. Rototilling sounds downright dangerous. Can you rototill with a jackhammer?

I have weed cloth, but nothing to hold it down with till I can afford that rock to go on top.

or newspaper can be done. It may have looked like hell, but the first year I put the paper down, I used milk jugs filled with water to hold them down----lots of milk jugs. Or you could use logs, or coat hangers untwisted and bent to secure the cloth down. There are probably hundreds or things that will work and are free. But the sooner you get this down, the better if you ask me. Don't worry yet about the rocks.

to hold down the weed cloth?

if the grass is in a sunny spot. The sun will "cook" the roots down 4-6." As a bonus, it will also kill any seed in the soil.

All you need is patience and clear plastic drop cloth. It would probably take all season.

A 10x20 area is TINY and easy to mulch! Here's what you do:
1) Cut the grass as short as you can get it.
2) Lay down a layer of cardboard or newspaper, overlapping all edges. If you use newspaper, make sure you put it down at least 7 sheets thick.
3) Cover with 3-8" mulch. This can be fallen leaves, grass clippings, chipped wood from a tree trimmer company, whatever you can scrounge up.

Your grass will be dead in a couple of months. Perennials with tubers may take longer. Rake off the mulch or dig it in when you're ready to do something else, but I have doubts about this pea gravel/moss thing.

If it spreads by runners, give up. It will never go away. I tried to eradicate bermuda grass in one place that I lived. It busted it's way through and around every barrier, and digging it simply allowed it to regrow from every minute piece of root left. Since it had spread UNDER the slab foundation, there was simply no way to get it all.