Autumn sowing of Beans and Peas

I'm going to sow some bijou today, I reckon.  Do you start them off indoors , or will they germinate in a cold gh?  Also how many plants would you consider to each MFB, knowing their ultimate size?

Hiya JJB

I've bunged mine in loo rolls one seed per roll. They are in a tray out in the back yard.

Last year I did my BB's in root trainers again outside in the yard, they all germinated and went well.