Only have experience with two of them.
Joined Next-door. Get a good overview of what are happening in the neighborhoods and tips for getting certain things done.
Open-door. If ubiquitous would mean death of the realtors industry. Visited a few houses by Open-door. Color scheme (gray 
) is always the same regardless of the layout and type of floor. These guys would put in the minimum price for investors like us to bid.
The two doors are based in SF. Clutter is in SoCal, and all the others are in NYC.
Haven’t heard of Better. Seems interesting.
I think the description of Better is not quite right. Only interest? Shouldn’t it be principal + interest. If interest only, would soon run out of funds to lend.