You can't advertise on instagram yet, as far as I know. They did start rolling out ads with "select marketing partners" last year, but don't think the regular small biz can start ads on it yet. Otherwise I'd be running them like nuts.
Instagram is the bomb when you are using #hashtags. Try hash tagging your city, or keywords like #cleaning #carpet blah blah.. We post a lot of pictures and junk on it and have younger customers usually say.. "I seen you guys on instagram!" I'm thinking of promoting our instagram through our facebook page to get people to start following us. I only have a lowly 100 followers on our @naturaldry account, but over 300 pictures. Once you begin getting followers and into #hashtags, you can start running contests, promotions, etc. That's when you really get going. Example: If we get #naturaldry rolling, it will appear in the main feed of an instagram user instead of them searching for the hashtag, because no one is going to be searching #naturaldry. Or if you run a contest, #naturaldrycontest could get leverage an start appearing in organic feeds on user accounts.
Try searching #carpet or #carpetcleaning hashtag on instagram, you will see cleaners around the country using it, correctly, and incorrectly.