first of all babysitters charge by the hour, home care providers charge by enrollment or day. A babysitter works only a few hours, home daycare providers work 40 plus hour/week.

I am in Ottawa and from the research I have done in my area the going rates are $35 to $45 per day. I am charging $35 (I am just starting out). At $35/day for a 5 day week ($175/wk) at 50 hours a week (10 hour days) I am only making $3.50/hour/child.
I only take kids 3 to 5 days a week, but they all pay $175/week, they pay for enrollment not by the day.

If someone asks when they call or email me I tell them my rates. Its YOUR BUSINESS not theirs, so you state the rates not them. if they think they are too high, next....you don't want them

When a parent asks how much break it down for them:
Food $5.00 to $10.00 per child per day (healthy food) sometimes it can cost more
Craft supplies $2.50/day per child
Education materials $2.50/day per child
field trips $0.50/day per child
15% taxes 5.25/day per child (income tax)
Equipment $2.50/day per child (purchase and repair)
Daycare insurance $0.50/child/day
toys/books $1.00/child per day
washing $0.50/child/day (sheets, blankets etc)

If they pay $35 per day, $25.75 goes to into the daycare, you are really only getting paid $9.25/day/child.

This is just how I have it broken down, you can break it down to what suites you and your needs/expenses are.

Make a website. I use weebly.com its very easy. its free but you can upgrade for a cost.
I also have a business email (hotmail) so people don't use my personal one. All my info. rates, policies are on my website, but you don't have to put up as much info as i do.

when i get a phone call or email i always ask these questions:
how old is the child
when would you need to start
has the child been in care before
when is the child's birthday
if it looks like the child would work, then i ask if they want an interview