I have excellent tenants in my SFH that is built REALLY close to my duplex. In the back, there's a 9' x 16' area of yard area which the current SFH tenant placed landscaping fabric down and now is desiring something to cover said fabric other than mulch.

Grass seed after the fabric is removed works well.

Ha Ha.

Of course since this is your good tenant maybe a little bit of river rock will look nice. Maybe even plant a couple low growing shrubs in the middle.

Astroturf or pavers

Landscape fabric is annoying. Covering it with mulch mostly just causes the weeds to grow on top in the mulch once the mulch starts to decompose. Then dandelions eventually manage to poke through. Then other weeds follow, so what one ends up with is weeds enmeshed into landscape fabric. A hot mess!

I'm assuming tenant put landscape fabric down to: a.) mostly cover a dead spot, and b.) avoid having to try to get grass to grow and maintain. So, I would recommend the very budget-friendly artificial turf otherwise known as indoor-outdoor carpet. Pavers are a bit more spendy, but make a better surface for a table and chairs.

Crusher run will just become a weedbed eventually, imo. Seeds blow in, take root, die, create soil, more seeds, more decomp, and again, a mess of weeds entwined in landscape fabric, and now there is a layer of gravel in there. Blech! And, when I say eventually, I mean 5-7 years at most.

With so much pressure to find quality tenants in a Blue State, I would expect fewer people interested in buying rental properties. So why go against the flow? I would think you would want to diversify your investments in places where your investment money is more welcomed.

Why did they put the fabric down in the first place? Was it because it was a "bad" area (no grass, holes, mostly weeds, etc)?

Hopefully they asked you before they did that but depending on what they (and mostly YOU) would like in that area, I'd work something out that's economical for you and maybe easy enough for them to take care of as well (assuming they are responsible for the yard care as it's a SFH)?

What's the goal? Cover up some ugly? Make an odd spot useful or an amenity? Provide an oasis?

I agree with Busy. Landscape fabric can be more hassle than bare ground.

River stone must be cleaned and maintained.

A few bags of fresh mulch each year is no big deal.

I like grass if THEY mow the yard.

If this is a patio style hang out spot, or a hard spot to mow, or maybe under trees so hard to grow grass, I like pavers for durability and no maintenance.

BRAD