Transmission trouble ahead? Hard to shift out of P cold

[wc1972]

My 99 camry has 130K on it. I bought it used at 75K and never did anything about the transmission.

I am really afraid of doing preventive maintenance as my past experience does not support that. I once had a fast-lube store change the serpentine belt, when they said the belt was old. Just a few miles later, I got slapping sound in the front bay. The new belt has threaded and make loud noises! Another round, I had a TOYOTA dealer changed the coolant, my car overheated 2 miles out of the dealership, turned out they mixed bubbles into the coolant when doing the change. So I tends to wait for the problem to appear and try to fix it.

It has been a while that the shift takes some efforts (like 5 to 10 pound.feet) to get out of the P position when the car is cold, but it takes no effort to do it after some driving and the car/transmission become hot/warm.

Is this a bad sign? Does it indicate that the transmission is going bad soon? Or it just means that ATF needs to be changed?

The stress has actually cost me $350, when the shifter cable broke one year ago. It was rusty, but I believe the stress must also played some important roles.