What should my blog be about on my website if I have a cleaning company?

[Hannah]

I own a pressure washing/window cleaning/tile and grout/floor restoration company. I used to do 4 other things. Unfortunately those 4 things are still on my business website. I wanted to think of some innovative ways to improve my website without messing with the placement codes of how my business works. Basically, If I just take out the 4 tabs all together it completely recks my website. So I got to thinking and I decided to make a jingle, blog, have picture tab of all the jobs done and the workers involved. I have yet to come up with a 4th idea for the 4th tab. Anyways, I heard that blogs can really help a business out. Business has been slow and I think making these changes will make it a more user friendly website. Any good ideas for what I should put in the blog and or an idea for what the 4th tab should be?