Hi tez,
I did the flyers myself using publisher and then printed them out, i spaced it out so i could get 2 flyers per sheet and cut the A4 into A5 using a guillotine, it looks proffessional enough.
I can only say don't over complicate the flyer make it short sharp and get your message across, you have to make it catchy because 99% of people will have a quick look before throwing it the bin. You have to make them want to read it.
I'm not sure though tez why you need flyers if you want to concentrate on office cleans, i'm sure somebody will correct me if i'm wrong but i don't think a flyer suffice, there are plenty of words of advice and help in the previous posts on this forum, just trawl through them all, you will be amazed at the knowledge imparted on here.
wayne