I would say not worth unless you want to stay in a local house for the night, are passing through and need somewhere to sleep, or just want to check out the process of the client membership before committing to a stay with them on your own.
I have done larger and smaller properties for this client. Once you know what to take the pics of, it can be done in 2 hours on property, and another hour or two at home submitting the report. It mainly depends on your photo labeling/resizing skills. There is almost no narrative required, but a long checklist.
The downside being the late check-in and early check-out for the client, plus it can only be you + one other adult, even if the house can host a party for 10. I think it works best when one person handles the checklist, and sends the other on the scavenger hunt for pictures. You could complete a 5,000 sq ft house in 90 mins that way.
We checked in a few months back at a $4.5M home at the beach, right at the allowed arrival time, finished the report and had time to walk into town for dinner, then use the pool, sit on the deck with a fire pit and drink the bottle of wine a previous guest had left (They are not supposed to leave that stuff for the next customer, but there were 2 bottles in the wine fridge for us.), then sleep in until 10 AM the next day, so it was a good mini vaca.
I don't want to poke the bear by stating what I get for the assignments, but decide what it's worth to you and put your bid in. I assume for the hard to schedule properties you can ask more. My fee covered our dinner in a upscale beachfront town, though...and I got free charging for my car, so that was a nice overnight trip for us that cost nothing in the end.
The first one I did had no heat in the pool or jacuzzi, so like a hotel, you take your lumps sometimes. We drove out to Palm Springs for that one and didn't really enjoy the property.