There is definitely an economy of scale, even just going from one house to two. We have had very good luck doing "clusters" of neighbors who were looking for the same services at the same time. We had one call us last fall and request deck wash/restain jobs for themselves and their neighbor. I estimated them both the same day, and we performed the work on both during the same week. It worked out well because the exposures of the decks were such that one was getting morning sun first, while the other was an afternoon sun, which we had to work with in the chilly fall mornings. It was nice to literally have my crew be able to walk 100 yards from job to job. In both cases, we also picked up interior paint work as a result of the washing. This is a situation where if we are inflexible and rigid, we could lose alot of work.
Anytime there is the opportunity to cluster jobs, it is silly not to explore it. Thats what we work so hard to achieve through yard signs and proximity marketing. When they fall right in our laps in clusters, its a really good thing. I'm not even talking 16 or 26 units. The whole small market domination concept revolves around securing as much work as possible in a confined and targeted area. There were several times last year when we had 3-4 projects happening within a half mile of each other. Great way to have high credibility and exposure in an area. Many of us are small businesses and this is such a great way to stimulate sales in a particular area.