Sportsmobile might be good choice. You'd need to talk to them about the seating.
http://www.sportsmobile.com/contact.html There's a very active forum here:
http://www.sportsmobileforum.com/index.php
Do you want the kitchen facilities? (fridge, microwave, sink, stove)
Do you want a shower in the van?
A Roadtrek 170 might be too small. It would be great for everyday driving though. You'd have to see one.
Would you buy a new Class B? If so, Roadtrek might be able to do something semi-custom. It would be ordered through a dealer but I think they'd discuss it directly with you.
Roadtrek is not promoting their 190 Simplicity but it my understanding that they will build one if a customer wants one. Link to Simplicity:
http://www.classbforum.com/phpBB2/vi...php?f=9&t=1697
I mentioned the 190 Simplicity because it would cost less than the 190 Popular. (less features) Brochure:
http://www.roadtrek.com/_images/brochur ... ochure.pdf
Here's another Class B forum to ask for opinions:
http://www.rv.net/forum/index.cfm/fusea ... rum/21.cfm Lot's of knowledgeable people there also.
I think the sofa seating would have to meet a safety standard to be allowed.
4 seats up front for driver and passengers might be preferable for driving around as a family. (edit: I just remembered you need seating for 5)