The upgrades to the 3 work areas cost $60,000, so that will take some time to earn. They increase their potential & how fast they progress through their careers.

The other items, such as treadmills, pools etc all add activities they can do, so they are off doing other things.

When a new generation starts, you have to wait for a potential marriage & then try for kids all over again.

I understand where you are coming from, but I find the replay factor higher in VF than VV who more or less looked after themselves once food was set up. You can even set them up to produce kids for you so the game could be closed for weeks or longer and keep going. If you close VF up for longer than a week, it's going to stop.