Vent Duct Cleaning..Costs...

[DD716TED]

I live in a manufactured home that I suspect during the building process, large amounts of sawdust and drywall dust were purposly deposited in the heating / cooling ducting before we were delivered the house. (This was that last home made by this particular mfg and we have discovered many other areas in the house that were obviously faulted by unhappy umployees that were losing their job).... Our house is always dusty... We have changed the furnace filters monthly, have cleaned the furnace/heat pump fan frequently, and are still getting fine white dust.. I have reached into the vent ducting as far as my arm will go and have found clumps of dirty building materials.. so I have decided to have the vents cleaned professionally. Living in a small community, I will have to call a vent cleaning company in a larger city... what would be a reasonable quote from them to clean the vents in a 1800 sq manufactured home? I want to be armed with a ball park price before I contact them.