If you have been away for two years then much has changed; price rises, delays, not just to the Scheme but across the sector.
The Merc CLA certainly was, and is, a fine looking car, powered by a 1.3 litre petrol engine, if you are looking at a petrol powered Vauxhall Astra the Advance payment starts at £349, much less than the 4k you would have paid for the Merc. Yes, the PHEV version of the Astra is an eye watering 7k AP.
In answer to your final question, you do not get any of the AP back, there is a Good condition bonus at the end of the lease, currently £600 for a three-year lease and £900 for a five-year lease.
Crunching the numbers is absolutely the correct thing to do as when entering into any long term financial commitment one should have all the information. Ultimately the question of ‘is the Scheme worth it’ is a personal one and dependent on many factors.
We are friendly group here, please ask any questions and do ask for advice.
WMC