First of all, sorry I haven't responded, I just have not taken the time but have read all the comments and overall it seems, everyone on here is happy to have their 3rd child except a couple of people.
@CandyLeBonBon hats off to you, I am not sure I would cope well by myself. At the moment as the nursery is closed, I have both full time and do find it hard, not unmanageable but all day, every day can be challenging.
@FakeFruitShoot 
@zoeydollie thank you! My first is lovely, second is 3 months old so hard to tell. I wouldn't have ever thought my first would be this lively given how chill he was as a baby.
@Echobelly my first is lively but I wouldn't say hard work. He's just one of those that runs rather than walks but he's just turned 2 1/2 and things are getting easier as I don't have to watch every step he takes anymore, on the playground or at home. Stair gate is off etc (for now until next one becomes mobile). Both are easy babies. I know what you mean though!!
@BonesJones that's what I'm worried about  I already think having 1 of them is like a day off in comparison to having to look after 2 although the baby is only 3 months but I do feel like that with the 2 1/2 year old as well.
@Livingintheclouds yes, the world is made for a family of 4. I would get the 7 seater Volvo. I've actually thought about it already even if we choose not to have a 3rd child. Financially, we're stable and with the youngest getting some of the nursery fees from the government, it wouldn't be an issue. By the time DC3 would be here, the oldest would be about to start school.
We did have a nanny for DC1 who I saw yesterday actually which was lovely. She wanted to pursue a different career which is fair enough but I'm trying to find a Monday nanny at the moment. I don't need to hire someone full time or for more days whilst I'm at home and I do like the setting my oldest is in, so wouldn't pull him. She used to work 3 days which in an ideal world, I would like to continue when I am going back to work next year.
To be continued (who knows when I'll respond) x