How much is the job worth?
In the past I have done jobs that bought equipment-exactly the same price.
You take the equipment as payment.
Google gutter vacs, find the one you want, the price if it-make that your quote to the customer.
If you're a bit skint-put it on a credit card, when the customer pays, pay it off.
If the customer says that you're too expensive-you've lost nothing.