I've got 3 DC, and although I believe only you and your DH can make the right decision for you, I thought I could offer some insight.
My DH comes from a big family, and wasn't really up for a 3rd DC at the time, but I def wanted one. I took the view that we would never regret doing it, but would more than likely regret not doing it.
As soon as DC3 was born, I knew our family was complete and
6 years later, I feel nostalgic at times for babies but never broody. It can be chaotic at times with 3 (I work too), and tiring when they are small of course, but it's wonderful, tbh, and I wouldn't have it any other way.
The downsides are - if you have a 'normal' car eg seats 5, having a friend over each is difficult; booking holidays/hotels for 5 is harder than for 4; you have to manage your time with each kid; you have to look out for middle child syndrome (I think mine def has it!); you have to budget that bit harder for food/treats and there is less to go around; the logistics of getting everyone to the right place at the right time can be challenging (and actually f*ing impossible sometimes - this has had me in tears before) .... but honestly, they are very minor niggles and are far outweighed by the huge amount of love and joy your child brings you.
I wouldn't let a small house influence your decision, and if you work for yourselves perhaps you could juggle your time to work around another baby.
That all sounds very 'pro' a third, actually, meant to be more impartial. But perhaps a tonic to those who have told you to stop at 2, if you feel you want a third. And of course, just 'cos it was right for me, it may not be right for you.
Maybe spend a day pretending you are preg with your 3rd, and then spend a day thinking you are stopping at two, and see how you feel afterwards?