Oh my goodness, everyone has had huge deposits!
I bought my house 3 years ago. It was a new build, and the builders were selling it for £125,000. I got it with shared equity, so had to pay the deposit/find a mortgage for £100,000.
I put down a deposit of 5%, and got a mortgage for the rest. Whilst the mortgage was 95% of the rest of what I needed to find, as I had shared equity, technically the mortgage was only for 75% of the property, so I have the same rate as someone who put down a 25% deposit.
The mortgage set up fees, which I think was in the region of £1,000), or whatever they are called, were added to my mortgage.
I got a fixed rate for 2 years at, I think 3.99% (which was about £424/month) and then, when I renewed, I got it for 3.79%, which is just a little over (400/month) - I could have got a cheaper rate, but that what have meant I would have had to pay a fee to get it, so wouldn't have been cheaper in the long run.
My solicitor cost about £800, moving cost about £45 (I hired a van and did it myself), and the only other costs were the furniture/carpets etc, as I was moving out for the first time, which cost about another £6,000 (I got about half of this on credit (sofas), my mum and nan insisted on paying for some (kitchen stuff) and I continued to save the same I had been saving each month for the deposit from the time I had paid my small deposit (£1,000, which was part of the £5,000 deposit) to reserve the house whilst the finished building the inside, and putting in all the bits I had chosen, like the tiles, cupboards etc.).
I don't have to pay the builders anything until 5 years, when I start paying interest at something silly like 1%, then have to pay the £25,000 after 10 years. If I sell the house before then, I have to pay them £25,000 or 20% of what I sell for (which ever is highest).