Washables are quite a bit of extra work. Anyone who says otherwise is fibbing. You need to be in a routine, the nappies take up more room, either stored or on a rack, they use very little washing powder (1/4 of usual amount and no softener) poos are icky once on solids liners help to an extent. You will have a bucket or wet bag to find a home for. Clothes will be a bit snugger, and vests and sleepsuits may be too short. You will occasionally run out, and will occasionally need to use disposables or there will be times when you need to tumble.
But, your bin will not stink and be full to bursting long before the bin men are due, your shopping bill will be 10-15 quid cheaper each week. Once you find the right nappy you are likely to have less leaks, so less clothes washing (especially the up-the-back explosions, you will likely need a larger changing bag, they are adorable, addictive, can be resold after, and can be used up to and including potty training and for subsequent children. They look lovely on the line, you will feel you are doing your bit for the environment, and other mums will be impressed. Dry pailing is the way to go, nurseries are more agreeable now. No need to use nappy cream, and you can use washable wipes, giving further savings.
When new baby will need changing up to 20 times a day, when on solids likely 5-6 times.
I found working full time it was pretty difficult to maintain the routine, so stopped, plus nursery had said 'no'. Hopefully if I cut my hours I will manage all the way through this time.
Think seriously before spending a small fortune on washables, and consider a trial first, but not immediately after the birth. Give yourself a bit of time getting used to your new person before adding more pressure.