You can do a lot on the inside for not much (in aviation terms).
New upholstery with new cushions from Tnwings about $700 for both seats:
New carpet from Tnwings about $300.
New wool headliner from Aircraft Spruce about $160.
Freshen up plastic ... a bit of elbow grease and a few bucks.
If you want to get fancy, talk to PlacardsPlus about dressing up the panel.
I have a G and like that model very much. It has the IFR shape panel but predates the awful "matching color" lower panel.
Reg