Anyone applied for a WHV with the minimum amount of funds?

I'll have more money from work coming in before I travel but what if I want to apply sooner?

The minimum amount for applying from the UK is £2,500 (£1,500 with a return flight booked). I keep reading about people recommending more (£10k for example) but some companies that help you with the application say the minimum amount is enough (BUNAC).

Obviously, I don't want my visa to be rejected.

Also, I was out of the country for a 2 month extended trip working remotely. Got home a few weeks ago. It's a sunny, popular location that is known to attract people looking for winter sun and my passport wasn't stamped. Will this be an issue? I've read that you need to be in the UK for 3 months.

Thanks