the NEC NP-V260X is still only a single chip DLP projector. It only has a contrast ratio of 2000:1 It's still going to have a lot of that light spill while it's black. I'm not saying it's not acceptable for many cases. But if that "light in the darkness" is a problem, you need to get into a whole different realm to get rid of it. That's not just the jump from a base level consumer projector to a entry level business model. You'd need to get into the pro realm to get to that point.
Here's a search that shows the least expensive projectors currently in this category. I've got some of these and their bigger cousins in my inventory and use them on shows all the time. They'll definitely do the job. But even I wouldn't set one of these in my front yard for a month.
Since not too many DIYers are going to drop 15k for a projector on their lawn, you're best off either hiding that light spill when you're not using it with a shutter. Or finding ways to mask that spill with other light.
In my show, I don't project onto things, I project thru them. (not technically, but it's easier to understand that way) For example, I've got tree cutouts with screen material stretched across a frame. The extra light that doesn't hit the tree "screen" buries itself into the ground from an angle that the audience can't see. I always make sure to cast that waste light into the sky, or onto the ground in a way it's not noticeable. I don't allow it to draw a box on a surface in front of the audience.
Another way to deal with it is to make sure your projector is projecting large enough to fill the whole surface that it's lighting up. If you're projecting onto your house. Make sure it fills that whole elevation of the house, and the other matching elevations have the same ambient light level. That way it's there, but it doesn't stand out because the whole house looks the same. This may require a brighter projector than you have. But those are a lot cheaper than the ones in the link above.
If you must have that box of light showing, try masking the edges with floods or other lights so that the box border doesn't show as obviously.
I use Panasonic D series projectors in my display. I've got some
PT-D4000s, one
DW5100 and a few
DW6300 units. I got them all used with lots of hours on them. They have a built in mechanical shutter so you only see any light at all when I want you to. They also have a bunch of other features that make them particularly nice for creative architectural projection such as edge blending and geometry correction and interchangeable optional lenses.