Can I use Authorize.net and let clients stay on site?

Hi My client wants to use authorize.net and have clients stay on his site, if use an iframe embed is this how it will work. If he wants his page to look secure then he can just buy an SSL certificate. Also I remember the paypal forms had an option to make a User-filled Price field, this is for invoices, so amount is always different, so user needs to input a unique amount for the sale and also need fields for name, email and address and then email customer an invoice, is all this possible?

Yes, you can indeed use our Authorize.net integration to collect payments on your form. When a form is embedded on a website and the payment form is submitted, your users will stay on your website.

The custom amounts option is available in all the payment integrations (Paypal, Auth.net, etc.). You can set this up by selecting User Defined Amount as the payment type during the integration setup.

Regards.