I have never seen any Prius changing battery after an year or so. This is highly misleading, and please correct you facts before pulling them out. Also there have been reported prius driven more than 300,000 KM on the same battery in Australia ! Heres the article :
Toyota Prius taxi tops 340,000mi, dispels battery myth
And further more if you buy a car in the first place you should check the car first. As for resale, you are living in a dream world brother if you think that your 1998 model civic is going to fetch you 8 lac, plus doing the math, even if its sold for 8 lac you are actually at a loss since the value of rupee has fallen down considerably and lets not even mention the amount of fuel youre car has consumed. Youre 98 civic must be one of a kind to give you a considerably good average of 13kmpl, still however there is absolutely no match of prius 20+ average with the type of accessories, drive, comfort and luxury prius has. Lets face it, Hybrids are doing good worldwide, especially Toyota Prius. The new model gives you an average 25 kmpl with the performance output of 140 horse power ! The accessories are those equal or on the par found in high grade luxurious vehicles. There is not a comparison drawn with even the latest honda civic.
As for maintenance, most of the people out there buy a second hand vehicle, change ALL of its fluids, change the tyres and usually even the rims, change the plugs, sometimes even the steroe... the list goes on. What do you do after every 5000 KM of driving your civic ? If you do not change its fluids.. rest assured you are poor at mantenance. There is no actual problem if you come down to solving the problem.
The only fact that might be a legitimate one presented by you is probably low availability of spare parts, once again there are tons of prius increasing on the road day by day. And if you can literally get a whole vitz 2006+ shape assembled from local markets..we are talking about a car here which was non-existent in Pakistan. Where will be the spare part situation of prius within the next 2-3 years ? Facts say the otherwise and you will see for yourself. Even now i do not think that you have an indicator light broken or a smashed brake light.. you would be left without options. There are many places to get them, once again if you are willing to.