Brother, I'm glad that you asked. The selection involves some basic considerations from personal and market perspectives. These include: Reliability, Economy, Utility, apart from Resale, availability and cost of spares. First off let me narrate my experience. My mother being aged needed a car with these characteristics:
1. Automatic Transmission for convenience, comfort and more focus on the road
2. Compact Hatchback for easy handling in traffic and while parking
3. Spacious enough for loading those monthly groceries or pick/drop duty of a platoon of grandchildren.
4. Fuel efficient thereby eliminating any need of CNG.
IMHO, the first two factors would apply to a lady of any age.
The Story of Our Vitz
Now, my mother asked for a JDM Mehran so I told her she meant a JDM Suzuki Alto. I took her to quite a few showrooms to check out/drive the Alto but recommended her the current Passo as being slightly better. Well, the Passo was more utilitarian and looked/felt solidly built but somehow she didn't feel comfortable while being seated in the car so naturally the driving experience was not commensurate. Finally, I made her check out our current 2010 Vitz. She was immensely and immediately impressed the moment she sat in the car. Comfortable seats, nice all around view (very important for lady drivers), and good layout of the dashboard and its controls. Okay, so far so good.
At this point when she was all set for the Vitz, I recommended yet another option: Honda City 1.3 Prosmatec. Took her to Honda Classic Islamabad for a demo but she refused. One: More expensive without any obvious advantages except the boot and 1.3L engine. Two: No airbags. Three: Uncomfortable seats. Four: I didn't tell her about the stiffer or hard suspension.
Next Stop: 2010 Toyota Vitz. Supposedly 4.5 Grade with Genuinely Verified Auction Sheet blah blah.
It has proved to be a real workhorse. Seen all kinds of road, sustained our dusty environment, hot weather and yet never gives up (Mashallah). Highly fuel efficient. Never required any mechanical or electronic work apart from the full tuning it had initially. Change of tyres, all fluids (engine oil, CVT oil, brake oil, coolant etc) and filters. The slight knocking issue remains which immediately vanishes whenever I fill in some Hi-Octane fuel. From groceries, school pick and drop, outings to even cement bags and sanitary fittings transporter from Raja Bazar to Bahria. It just does the job.
In your scenario, i strongly suggest you take our sister to check and try out both. While it's going to be you to ultimately decide, there are pros and cons to everything. Personally, I don't like the Pino's shape. It just seems out of place. Do reason with your mechanic as to why he is preferring City over Vitz. Because of his experiences? Or Maybe he has got a secret seller looking for a buyer (you).
To sum it up, both are capable cars (1.3 Vitz and 1.3 Honda City), well made and suited to our environment. But both would offer trade-offs. Relate them to your personal preferences and budget and you will get your answer. City will experience a dip in its resale value as soon as the new model launches (probably sometime mid next year) whereas 2007 Vitz has seen and had its share of price drop and is probably stable enough in the resale department.
Spare parts are easily and adequately available (both new and used). Cost wise parts are almost equally priced but please don't take my word for it yet unless someone here gives a full experience. Mechanics are well conversant with working on both. So, finally, it might be a tough one but it's your call.
If the difference is more than 3 Lacs, look elsewhere for a nice 1.0 Vitz. But I won't compare a Pino to a Vitz.