The profit depends on:

1. where you get your services from (hosts charge different amounts)

2. How many clients the customer has that actually pay and stay dedicated to paying.

Them are only a few, there are many different prospecting factors in what decides the resellers profit. There can be some huge profit margins depending on where you get the package and how much you have to pay. Are you overselling or underselling. Its really hard to figure out per host. I don't think they would tell you if you asked either Just my opinion.

It can be like 60 to 70%.
according to me best reseller hosting site is greengeeks.com

The more that you are willing to spend, the more you are going to be able to make. I would start small with a reseller just to test the waters, and see how you are going to like running the operation. Then upgrade it as necessary, once you have gotten your feet wet.

This will be different with every host you ask.

I would say that the Hosting business is so over-saturated with hosting companies that it's ridiculous.. However, you could get started on a good VPS for under $25.00 and easily make $50-$100 on that single VPS. Granted, you would need to have a very good niche / market to offer to.

I have had a great deal of success advertising to my local businesses and doing just fine maintaining a healthy profit margin

I find enticing new customers in with one time discounts works best such as a free month or reduced rate first month