EA looking for holding deposit

Hi, I have been been morgaged approved in principal, but my 3 months has since elapsed, so I have to go back to the bank now to renew, my broker has said there should be no probleam, but in the last couple of days I have had an offer accepted on a house, and they seem to be keen to sell, they want a holding deposit on the house. My question is am I in a position to put this deposit down, as I thought this would have been part of been morgaged approved and the bank would look after this, but as I am only approved in principal properly not so. As the conversation was only a brief one with the EA, I dont have a lot of details regarding the deposit, whether its refundable or not. Is it common to have a holding deposit when purchasing, I know when renting it is but never heard of it when purchasing, thanks.

The deposit to the EA is fully refundable; and wholly subject to contract.
You can pull out at any point without even giving a reason up to the point you sign on the dotted line.

The deposit you pay to the Estate agent is the booking or holding deposit to keep the house for you until the sale goes through.
It is usually a couple of thousand and is fully refundable and the EA will give you a receipt.
Next step is you sign the contracts when they are ready (like a few weeks time) and pay 10% of the price (this is also called a 'deposit') but this one is non-refundable once you've signed the contracts. This 10% would be less the holding deposit you've already paid to the estate agent.
I think nowadays the 10% is negotiable, some people pay less at the contact stage depending (talk to you solicitor about this).
Then the final stage is Closing, which is the day the funds go from your mortgage provider to the seller's solicitor (called 'drawdown' of the funds), and the day you get your keys.

Just to note: as well as getting your mortgage reapproved, you need to work on getting quotes for life insurance, because this can seem straightforward, but sometimes there are health forms to get filled in by GPs etc which can take more time than you would ever think. You don't need to take the life insurance offered by your Bank/Broker, if you can get the same cover elsewhere for cheaper.