There is a band of products within the handheld multimeter market which, regardless of the manufacturer, are all based around an IC family from Taiwanese manufacturer CyrusTek. You can see this in Dave Jones’ multimeter teardowns – nearly all the units he opens up have a CyrusTek IC running the show. So in terms of feature sets they are all on a fairly level playing field; the price spread mostly comes from build & component quality and the user interface design.
If you read the datasheet for those ICs – the ES519xx series – you’ll make the interesting observation that they all do RS232 compliant output. So a vast number of multimeters – quite possibly yours - are capable of serial communication, but most manufacturers don’t break it out to the front panel for you. Read more of this post