Maintenance questions

I am in the process of buying a 2018 sienna xle awd. It will be silver certified and I asked about the transmission and diff fluid, dealer sold originally and has no record of it being done. I am being quoted about $480 to have both done. Wondering if that seems reasonable for a shop to do it prior to purchase. The van has 68k miles on it currently. I’m thinking I’d like to keep it for a while and would just rather have it done before i pick it up to be good for some time and wondered everyone’s thoughts.

Thank you!