MARBLEHEAD- The Fair Housing Committee is going shopping for some affordable condominium units.After a brief discussion, committee members received the support of selectmen Wednesday evening to use an estimated $114,000 to purchase housing – a two-family home, for example – that could be converted to two-three affordable units.Committee Chairman Dirk Isbrandtsen said the town has accumulated about $67,000 in federal housing assistance through the North Shore Housing Consortium during the past few years and will be eligible to receive $47,000 this year.Although Marblehead has less surplus land and less available housing stock than many communities, Isbrandtsen said the market has softened a bit recently making a housing purchase possible.Once housing has been purchased and converted it will be made available through a lottery. Although the deed on such a property has restrictions barring its sale for profit Isbrandtsen said it is possible that if a purchaser remained in the home for an extended time they could accumulate some equity.