You have answered your own question
NExT
If it is just Start your car, an easy option is the “EasyGuard”
and there are some more in the project section
Here is a couple of starters { no pun intended } for you
https://forum.dangerousthings.com/search?q=easyguard
https://forum.dangerousthings.com/search?q=keyless
It sounds like you are not confident enough to do it yourself, but if you give us some info on your current car lock /unlock and start system, we could probably narrow down some options for you.
From there, you could get the parts you want, and we could talk you through the basic setup, you could do most of the install, then get the Auto electrcian ( Or similar ) to do the final connection to power, you will save money, get to learn and get the “Pro” to do the final hook-up, to keep you safe