DH and I are both eldest of three, and wistfully used to imagine our own three child family back in the early 2000s when we were young and naive and carefree.
Our reality is that we have two DC, both boys, 6 and 11, and we don't want any more. Financially we are just about getting back to normal after I took mat leave with the second, mainly due to balancing part time hours and childcare fees, but a large part was down to me not moving up pay grades as i would have if I hadn't been off on mat leave and then part time for a few years. A third would mean going back to the start of all that, and though we could just about do it money-wise (we've done it before!), neither of us could justify putting our existing two through that more precarious financial position just because we wanted another baby. I don't want us to be stretched to the limit, because all the love in the world doesn't keep a roof over our heads if finances go tits up for any reason, and covid has definitely hit that home for so many families.
I had a very hard first pregnancy with DS1, and a totally fraught but physically healthy one with DS2. I'm healthy, reasonably fit, and luckily don't have any lasting injuries from either birth, but there are no guarantees and I'd rather not put my body through something as physically tricky as pregnancy again.
My two get on beautifully, not a brag but honestly I'm so lucky because I grew up in a household of sibling rivalry and competing for attention, and I'd absolutely hate to recreate that dynamic by having a third and screwing things up. In my opinion, DC's relationship wouldn't improve by having a small baby chucked into the mix, and with that knowledge I wouldn't do it.
And finally, perhaps most importantly, neither DH nor I could possibly justify making another brand new human being in the current global climate situation. Two is enough. I have neither the right nor need for three children when the planet is literally on fire.
If I was in your shoes I wouldn't have a third, because you never know what the future holds and I'd always be secretly worried about money and space, but obviously only you and your DH can make the final decision. It's not without its pangs of 'what if?', and we met a lovely new mum with an eight week old the other day in a running shop and both just went a bit misty-eyed at how teeny and small her daughter was, but that's fleeting. There's also a wonderful sense of happiness that we're done having babies and can get on with this next chapter of our lives together.