Thats well cool PW, you could make them to sell I reckon!
We've a bought 'bug hotel' that didn't see much action last year, where they are sited seems to be important. I thought I'd put it somewhere a bit protected, but I think the insects took that to equal dark and gloomy - they need to be in sun I think. I've not checked our homemade one for a while, its down the bottom of the garden. I'll hunt it out and check it tomorrow cos the year before last it had lots of its holes blocked up with mud and occupied.