You need to understand equipment rental rates well to set your prices right. There are ways to determine the right price for your rental equipment: calculating cost plus margin and using that as your starting point, researching the market and positioning yourself somewhere along the spectrum. Most people who rent equipment would prefer to get the lowest price possible, and it's important, to be honest about what you're willing to pay. You can probably find a better deal somewhere else—and you should look into that option.
To set a fair rate that allows you to cover your costs and make a profit, you need to consider some things first. It's important to know what equipment you'll need to purchase and how much you'll need to pay for each piece. You also want to ensure you have enough equipment to meet your business needs and that your purchase equipment is reliable and durable.