One of the VBA guys will be along, but simplistically, I guess you could do something in Excel and copy/paste it in to MSProject



ie create a table with all the options in the build sequence, and select those that you need in a column called "required"

Filter on those required (or use a pivot table) and paste the resultant data into Project

Ref Task Duration Required
1 Is planning permission needed 10d Yes
2 2 bed house 110d
3 3 bed house 120d Yes
4 4 bed house 140d
5 Garage 10d Yes

Thanks...I hadn't considered that approach.