Looking for an RZR: new vs old?

Hello everyone;

My first post here as trying to get some answers;
Here’s the long story short:
New to the side by side world. I am contemplating to get one soon for several reasons, currently i am building a buggy and don’t see myself finishing it in the next 4 to 5 years. The most important reason is that my 10 year old digs the crawling sport and looking forward for me to finish the project so we can hit the trails, but there goes that idea. I have promised him if he improves with school grades (huge struggle for him but really kick but this year) I will buy one so we can both enjoy it. Well my time has come !

The biggest dilemma I have is (from reading) is that used ones have more than 1500 miles requiring a complete overhaul including engine work. I sort of know the answer to this, but is it really worth buying a used RZR (fix it and upgrade) vs buying a new one so I can go out and play?
I don’t mind fixing small things, just trying to do the right math as (again) don’t know much about the side by sides!
In advance, sorry if this already had been posted, but need some feedback !
I already started fixing my trailer and getting a new registration, when school is over, want to surprise him when I open the garage !
D.