Transmission problems and costs

Anyone got advice?

I have a 2002 Saturn SL2. I bought the car new, and have had all recommended service done on it at the Saturn dealership where it was bought. It now has 86,000 miles on it and the transmission has failed. The dealer recommends a 1/2 rebuild + some other 90,000 mile service for about $1500. Anindependent mechanic recommends and has a completely rebuilt trans mission with 58,000 miles on it. Price to install & do the same 90,000 service, about $1700. Which is the wiser choice? ALSO, a friend has offered to pay for the repair, give me an additional $2000 and his 1985 Pontiac Bonneville, which has about 115,000 miles on it, a new transmission and radiator, but needs new tires and gets poor gas mileage. Should I take his offer or repair and keep my Saturn?

Thanks to anyone who knows cars for their opinion.

Sincerely,

Marie walker