By way of a preface, I have no experience with this firm. Everything below is therefore essentially reasoned opinion.
Part of their business seems to be acting as a middle-man between an inventor and a patent attorney. They imply they can charge a lower fee than if you commissioned the services yourself.
From their FAQ:
Can InventHelp help me patent an idea?
For clients who want to know how to patent an invention idea, InventHelp can refer them to an independent licensed patent attorney to provide a preliminary US patent search and opinion. Based on the opinion, the attorney may then help prepare and file a US patent application for the idea with the US Patent and Trademark Office.
Why would an inventor choose to work with InventHelp?
For the same reasons consumers buy any service: convenience and cost. For example, in order to obtain similar services as those offered by "The Invent Help People," an inventor would have to [do a long list of things]. These services purchased individually by an inventor acting alone could cost much more than InventHelp's fees.
Therefore, they probably could assist you.
However, as far as I could tell, they give no details about what their indicative fees would be. I would therefore be skeptical about such claims.
Moreover, I would be worried that their and your incentives aren't quite aligned: if they take a margin between the attorneys costs and what you pay, would they want to depress the attorneys costs to maximise their margin? So they would be incentivised to choose attorneys who have lower fees, regardless of the outcomes.
I would therefore caution against using them, at least without some serious consideration of the alternatives.
If you're serious about getting a patent, I would recommend contacting one or more patent attorneys in your area, and have a discussion about their costs and what you can expect. You would typically want to find someone who has at least some knowledge of the technical area of your invention, and also someone who you find reasonable to work with.
Often, smaller firms or solos will have lower fees, especially if they are based outside of major cities, without necessarily jeopardising quality.
Is a patent even appropriate?
If you have limited means, then I would recommend giving some serious though about why you even want a patent. A patent has three business purposes:
1. to prevent competitors (by passive dissuasion or active litigation).
2. as an asset to be sold; and
3. as a marketing tool.
Is the likely cost of the patent going to present a good return on one of these? Or would the money be better invested in the business itself.
An anonymous editor of this post suggested that the USPTO has information on scam firms. It appears to be here. I note this merely for completeness: I take no view on whether InventHelp is running a scam or not.