To economise, you could purchase 2 x Britax First Class Plus car seats. This is a rear and forward facing car seat, which will last you up to 18kg, a group 0+ - 1. When choosing a twin pushchair you need to look for something that fits your lifestyle: something that is practical and easy to use, lightweight and suitable from birth.
Ones to check out are Baby Jogger City Mini Twin, Out and About Nipper 2, Maclaren Twin Triumph, the iCandy Peach Blossom (Tandem) and iCandy Pear (available in our shops). The Maxi-Cosi car seats can fit in iCandy pushchairs, and can also be used with an Isofix base. (Please check that your car is Isofix-compatible.)
For the first few months, twins can go into two Moses baskets. This gives you the flexibility of moving around the house, and you can put them in the same room with you. I'd recommend swaddle blankets such as Grobag Woodland Friends in the first few weeks rather than sleeping bags, as these have weight restrictions.
If you're thinking of putting your twins in the same cot, we recommend they sleep top to tail.
You'll only need one bath and changing table as usually you'll be bathing and changing the babies separately. A bath support is advisable as this allows you to have your hands free.
We'd recommend buying a Baby Bouncer and a Gym, as this will give you the option to swap the babies' activities.
You'll only need one steriliser for twins. Bottles and teats (once sterilised) can be shared, as can cutlery, weaning pots, and bibs.
Good luck with your double bundles of joy!