Citroen Berlingo or it's Peugeot twin would fit the bill. Usage though suggests you should avoid diesel but petrol engines may be rare amongst examples in your price range. At least until diesel began to come in for a pasting most buyers chose the diesel.

Budget remains the same. Decided it will probably be best for me to take the current family car for work and buy a larger car as we're going to need larger soon anyway. By not too large I mean I want to avoid the MPVs that look like mini buses, and if I'd prefer just the 2 rows of seats. Hope that makes sense. Thanks for your advice

Fair enough (your post to SLO nails it), and probably a good idea if your family is getting bigger. I would say that the suggestions of the Mazda5 (nice driving, reliable [petrol] engines and those handy sliding doors for car parks and tight driveways etc) and the Honda FRV seem perfectly reasonable. Stay away from diesels as explained before on the other thread as short trips only ruins them (some more quickly than others). Check the load space, child seat attachments all fit and the boot lip is low enough for your needs.

Would you prefer an MPV over an estate, which can give more load space. In any case, I'd go for the mid-range models that have less gadgets to go wrong and higher profile tyres (say 16in 55-65 profile) which still handle fine but give a decent ride over the bone shaker 40-50 profile versions, last twice as long and cost half as much to replace (205/55 R16 is the most common and the cheapest of the 16in ones) - very handy if you're on a tight budget.

Mazda 5 a good car with advantage of sliding doors. I had one for a bit, remember it being quite narrow inside without a proper centre rear seat. It was a few years ago and I maybe wrong but check it’ll take three child seats, I’m not sure it will.

Perhaps (my slow memory now does recall another thread with comments to that effect) - maybe the OP will be lucky, in that their eldest child may not need a child seat by the time No.3 comes along. For all the advice we all give on the forum about performance, handling and reliability of cars, its all a bit pointless if you can't use it for its primary purpose!

I remember being laughed at by colleagues when I took my holiday stuff (suitcase, box of provisions [I go self-catering and need to bring certain foods but also certain k******ware not provided], golf bag, trolley, shoes and umbrella plus the usual holiday/long trip/car stuff [foot pump, etc]) - empty suitcase and box of course - with me in my little Micra when I went looking for a replacement (12+ years ago), so I could see whether I could get it all in the boot of cars I was looking at without having to put the back seat down (safety/security reasons).

Definitely worthwhile, as some of the cars I looked at were very good on many other fronts, but the boot was too small. Even the Mazda3 hatch (I bought the saloon which has a 405 ltr boot) didn't have a big enough boot (about 40-50 lts smaller) and I would end up with a similar problem as with my Micra with having to either take the parcel shelf out/put the back seats down and have loose items (potential missiles in the event of an accident) in the boot area and on the back seats.

So many people just visit a showroom/forecourt and have a short test drive, rather than a good look around the car (including trying to get the drivers seating position right for all drivers), checking to see if it meets all their potential needs (and especially must-haves) as well as a decent length test-drive on different types of roads and speeds for all the car's drivers.

I would definitely recommend this to the OP, as I've come across many people who've had to PX their shiny new car just after a few months because it was uncomfortable or didn't have a must-have feature (because they didn't do their homework and/or forgot/couldn't be bothered to check). This can prove VERY expensive, even for people buying on a budget.