Module to fit a 'lease' style business

Hi, I was hoping those more experienced members might be able to recommend a module in ERPNext that would fit a business type that leases products. I’d like to be able to customise an existing doctype, if possible.

So far I’ve been looking through the Stock/Item doctypes, and I think that could work. If there’s something more suited to a lease arrangement though I’d love to hear about it.

Many thanks.