With monarchs soon to be possibly listed as Threatened, I'll do what I can to help them on my property.

Here it is:

You would be hard pressed to build one for that cost. It would take some time and skill to build one of those not mentioning having access to the materials to build one. I have had a few but never have seen butterflies coming and going for them.

To my knowledge “butterfly houses” are to help provide wintering place for those few species that hibernate thru winters. Proper location is key and MAY only be used if other better natural sites don’t already exist. They are of no aid to Monarchs. Encouraging or planting as much milkweeds as you can is better. And this will only help if enough is sustained with habitat along their migration routes and not wiped out by ag pesticides or destruction of safe wintering grounds. Much currently being overgrazed by cattle that eat them like popcorn when they temporarily fall to the ground from their tree roosts on cold mornings.

I'm not optimistic but am giving it a chance nonetheless.
There are a lot of species of butterfllies. I'm unsure how different each type acts or if most make good pollinators

I'm not discouraging any effort to aid wildlife because I've tried most everything just passing along my experiences and info gathered on my efforts. Mourning Cloak and Comma are the two most common wintering butterflies in our/your area. My wildlife improvement efforts have been most successful when enhancing what is natural and native to my property. But some artificial improvements have provided amazing results within what nature allows them bird houses, bee houses, drumming logs, squirrel boxes, etc but have been limited by natural setbacks like severe drought, weather disasters during migrations increase in marauding BEARS, lol. I have piles of next generation designs attempting to make a better whatever(not just my trapping accessories). For me that is the fun and the challenge and hope it will always be till the day they spread me on the land I trying my best to steward. As a Biologist I like to have a little science support many of the things that are marketed out there. Good luck with your efforts.

all 4 species of Bushfoot butterfly overwinter ie mourning cloak Comma etc loss
Comptom tortoishell mass together as well as mourning cloak 100 to 200 in one spot is common when you find them. The best way is when you see one flying in a warm day in Oct-Nov to follow their flight path back to the overwintering spot. Of the two colonies I have marked and re-captured in the spring 97% losses were found. One other colony was destroyed when a shrew got into them =100% eaten

The Texas generation is the first one for the year and the northern latt. are 2nd and 3rd generations for the year of the Monarchs