Perch Shop for Rentals

Hi,

I have a project for bike rentals and I'd like to use Perch Shop for this.

A user would typically wish to rent one or more bikes for a number of days, along with a number of possible accessories for the same period.

In an ideal world I'd like to manage availability of the products within Shop using a calendar of some sort, but as I understand it Shop has no native mechanism to handle availability (e.g. via an availability calendar). Is this correct?

Leaving aside the question of availability, is there a mechanism within Shop to handle the purchase (rental) of a product for a specific number of days? So could I assign a multiplier (number of days) that is subsequently applied to the cost of every item in the cart (i.e. bikes and accessories)?

And a further question... is it possible to use Shop with deferred payment? So essentially using Shop to store the user's order request but not process any transaction, with a later possibility of requesting payment from the user later?

Many thanks in advance for any feedback or suggestions!