Now this is a topic I can help out on, I have spent many years in recruitment woo who something i know about,
Temping someone through an agency can seem expensive however if agencies actually took the time to explain what makes up their fees then I am sure more people would appreciate the value behind them.
A temporary worker is paid in accordance to the salary you dictate, so for instance if you employ someone on £18,000 and your weekly hours are 35 then you hourly rate you pay them is £18000 / 52 weeks / 35 hours = £9.89, an agency will then add 12.8% Holiday Pay and 8.3% Employee NI, I believe these fiqures are set in stone, the real area you want to concentrate on are the agencies margins (what they make) my current agnecy charges a £2.70 margin so in total for a £18,000 person from an agency it will cost you in the region of £15.71 per hour, I am rusty on the temporary side so this is a guide for you, now the benefit to you is save on payrolling expenses, headcounts etc etc etc
If you decide to offer a candidate who has been temping through the agency a job with your company then the costs can be anything from free to 20% of salary plus, if you want my advice I would advise you if you use an agency to lay it on thick at the start and say to them "yes" we will use you for a temp however if the person goes permanent after say 12 weeks and we offer them a permanent contract we want a reduced or free of charge policy, if you are difficult with them at the start consultants nowadays will give in to that, especially when they have targets to hit!
However I would like to just say that the good and these also generally seem to be the independant agencies actually can do a really good job, I have several massive companies who will only use me for their respective recruitment hence the fact why I am setting up on my own away from my company because its about dealing with me rather than my company.
When you think about the costs involved with activity accounting rather than just the charge for posting an advertisement it can work out a lot more, also if you put two repeat ads in the paper and get nothing you could spend a fortune, with an agency you pay nothing until you find the right person and then after that most agencies have a 12 week rebate policy, imagine a director on £50000 wasting his/her time pre-selecting 30 cvs for one job, how expensive would that be?
My advice to anyone is, firstly look and see if you can internally promote and then recruit for a lower level of staff, find a consultant who listens and understands and who is willing to visit you, and set in stone a mutually beneficial but realistic fee structure with them and in general you cannot fail, if personnel are the building blocks of the business how can you afford to look for a cheap, cut the corners solution?
If you need any advice let me know, its just a matter of getting the best deal to suit you, I am not in catering recruitment so i will not be touting for business, just some freebie advice