baby monitor recommendations

We have a 2.5 years old and expecting twins soon. We want to invest in a baby monitoring system for all 3 kids (maybe we do without monitoring the toddler if needed). Ideally we find 3 cameras that can connect to phone and also to a wifi independent portable screen. We want the monitor and the app to have split screens option for watching the 3 cameras simultaneously. preferably no subscription is needed.

I have looked at multiple options but the reviews are always putting me off. If anyone has personal experience with any system that does the job well enough, I will greatly appreciate the recommendation.