Hey Clean Lawn:
Tiedeman is right about looking at it from an hourly perspective. However, most customers will balk at hearing you're going to charge $50/hour to rake leaves. They would much rather hear a flat rate. Your flat rate, of course, is derived from an hourly rate. Tiedeman is also very correct that a 2 hour job can quickly turn into a 5 hour job. So, if your rate is $50/hour and you think it's a 5 hour job, tell the customer $250.
Until you gain experience, it's hard to tell how long a job will take. Try some experiments. Go into your own yard and mark off a 20' X 20' area. Then practice raking that area even if there aren't leaves there (yes, your neighbors might think you're crazy). Rake the imaginary leaves onto your tarp and then haul it away...or bag them. Time yourself for each task. This will give you a rough idea how long it will take you to rake and gather 400 sqft. of leaves. Then, you can apply that time estimate to a larger area by multiples. Same way for cleaning beds, etc.
Here are just a few questions to think about that can dramatically influence the amount of work for each job: Do the leaves need to be hauled away? Hauling will ad tons of work to a job unless you have an enclosed leaf trailer with a vacuum mulcher. Is there a mulch pile on the property where you can dump them? Do they need to be bagged? Do shrub beds need to be cleaned? Beds can easily account for 1/2 of your time to do them properly.
Hmmm...let's see...what else..Oh, yes: Tools of the trade of a leaf job:
Two people. An extra person can more than half your time. One person with a backpack blower and the other person with a rake working in unison will greatly speed up your work.
A large tarp. Rake the leaves onto the tarp then drag the tarp to the mulch pile.
A slender shrub rake...great for raking beds inbetween bushes.
Gloves. rakes wear quick blisters in your hands.
There's something else I like about Tiedeman's response. He said don't be afraid to turn jobs down. That is excellent advice. When you're new in business, you want all the work you can get. But then you end up working for much less than you are worth if you take every job that comes your way. Bid right and if the customer won't pay walk away and bid on the next yard.
That's all I can think of right now off the top of my head.
You are asking good questions. Take a minute to visit this website: www.StartALawnCareBusiness.com
The package offered there is my material. I think you'll get a lot out of it. There's even a section dedicated to this very subject of leaf raking. Hey, it even includes a story of the time I accidently caught a pile of leaves on fire in a customer's yard. LOL.
Best of luck: