Tomorrow I'm going to look at a https://www.facebook.com/marketplace/item/1183901298909438/ The owner stated that he had seen some transmission issues with the car. I followed up and he said he saw slipping in first gear and weird issues on the highway. He says that 1000mi ago he did a flush/fill of the transmission and the problems haven't returned. (I will confirm this when test driving, and with my OBDII reader) The asking price is about $1600 below fair market value, but if the transmission is junk, a remanufactured transmission is about $2200.

1) Are there any common issues with the 2008 GTP that I should check for when I look at it?
2) Any thoughts on how likely the flush/fill will give the transmission another 1-2 years of life? (If it gets 1 year before needing to be replaced, I would be happy with that.) Do these transmissions have any replaceable parts (solenoids, pressure transducers, etc.) that I could replace to help the transmission last longer? (My skill level can handle any parts I can replace by removing the pan, but not opening up the transmission more than that. I would only do this if the OBDII codes suggest a certain part was the issue.)
3) While I've replaced transmissions before, they have all been RWD transmissions. Are FWD transmissions significantly harder (or easier) to replace? Is anything difficult about the 2008 GXP for a transmission swap?