My dad has been using a wheelchair for the past 2 years after he met with a car accident. He has been using a normal wheelchair. Last day he asked me if I could buy a motorized wheelchair for him, so that he could travel with more ease. So I have checked a few motorized wheelchairs online. I like Trident 20 inch front wheel powered wheelchair from online shop Agecomfort the most. Any Suggestions will be good about the particular model or any other,
quickie-wheelchairsinfo/measuring-guide
http://www.mccc.edu/~behrensb/documents/210wk15WCFit.pdf
If you know his measurements and weight, you can pick these chairs up second hand for about $200 locally.
With a prescription from an MD, you can rent a new one, and your insurance might even cover 80% of the rental.