2008 Nissan Rogue S--Needs Work, But Well Worth the Repair

This 2008 Nissan Rogue S is clean inside and out. The interior is in excellent, showing very little wear and tear. The seats, carpet, and the rest of the inside are clean and free of rips. The exterior is in good condition. There are a few minor scuffs/scratches, but the paint still shines up nicely. Overall, a really nice-looking vehicle, but it does need mechanical work.
The vehicle ran and drove perfectly up until a few days ago. Now it doesn't move at all. The check engine light is on Code P0720 (Speed Sensor). The speed sensor is located on the outside of the transmission between the transmission and the axle. However, the mechanic isn't sure this would resolve the issue. It's a possibility the transmission would have to be replaced; therefore, the owner opted to try and sell it as-is before doing any repairs. The vehicle is currently at a shop.
The vehicle is really nice, and it's definitely worth repairing--even if t needs another transmission. However, if turn out it doesn't, then you would really getting a steal.
Thanks and Good Luck!