has anyone ever had any experience of steam cleaning furnishings, in particular curtains and a mattress

i have been offered a new matress but due to how it's been stored and because some of the packaging has been damaged it's a little dusty and i wondered if it would steam clean?

the same for curtains, mine are dry clean only, the cost of dry cleaning is a whopping £45 per pair (there's 3 prs) [msnoo] and i was wondering if i could steam them as they are not marked, just need a freshen up?

thanks in advance for any advice

mizzy