What is the difference between c4 and sd connect?
I bought my 2015 ver C4 w. wired china multiplexer 5 yrs ago from Aliexpress vendor 'OEM Scan Tool.
Most all of the Aliexpress listings for C4 have gone to SD Connect wireless multiplexer which adds some cost.
Another factor to consider are your inclinations toward 'geekdom'. My C4 setup was a HDD set up for a Delll D630. I purchased the cables, the multiplexer & the HDD. I had to add D630 laptop, install the HDD, get it booted, then get some support form Aliexpress vendor via Team Viewer to get all the keygen stuff done and then I was ready to go. Pretty standard stuff for this. That older C4 setup was running on a pretty heavily modified WinXP OS that involved 4 partitions on the HDD, etc. I later cloned the HDD over to an SSD (highly recommended to get an SSD). With that old weird XP multi-partition setup that gets a bit geeky to deal with.
The later system on Win7 doesn't use that weirdness and is cleaner/easier and less geeky. This probably increased the cost a little also.
I put about $530 total into my system.
There are 3 links below that range in price depending on how complete you want to get the system, but that getting started cost is moving up to $750~$850.
One other suggestion aside fro the SSD is to get 4GB RAM in the laptop. The cost of the RAM is negligible, but you'd need to ask to make sure you get it.
860.0US $ |2019 Hot MB star c4 SD C4 with Laptop De11 d630 DAS software HDD (03/2019) Diagnosis Tester Xentry key generator as a gift|sd c4|mb starstar c4 - AliExpressSmarter Shopping, Better Living! Aliexpress.comwww.aliexpress.com
273.6US $ 4% OFF|CF52 laptop with MB Star C4 SD Connect SSD 2021.03v HHTwin Diagnosis System Compact 4 DTS8.16 for Mercede MB Diagnostic Tool|Car Diagnostic Cables & Connectors| - AliExpressSmarter Shopping, Better Living! Aliexpress.comwww.aliexpress.com
104.49US $ 19% OFF|MB Star C4 Sd Connect Diagnostic Tool Wifi Star C4 Multiplexer with Cables Star Diagnosis C4 Software HDD DAS System|Car Diagnostic Cables & Connectors| - AliExpressSmarter Shopping, Better Living! Aliexpress.comwww.aliexpress.com
Hope this helps.