Right now, you can't put holds on transfers. They happen automatically on Mondays. You can speed it up but that's it.
Jane and Diana- I'm thinking the that Etsy's eventually hoping to take over our finances for us. I, too, would like to be able to carry a balance in my shop payment account so that I could use it when I make Etsy purchases for things like packaging and supplies. I don't Etsy's shipping label option though because Paypal is still cheaper. I don't get a ton of sales so I have no problem typing in addresses.