Coming from someone from the salt belt, that is not bad at all for a 2007 model year. If you ask someone from AZ, CA, or TX that would be too much rust.

2nd picture from the last is a bit concerning, not sure if it is surface rust or not. If a screwdriver goes through it then I would pass on it. If it just surface rust, I would clean it up and apply anti-rust on it. Fluid Film, WoolWax and KROWN are some of the well-known brands.

 

I don't see anything alarming in those photos. Brush the loose rust off and apply protectant as @Azulete said.

 

X3, Also the Tundras didn't have the frame issues the Tacoma experienced.

 

in 2000 - 2003 they did. In my experience, any toyota truck frame can rust and rust bad. be if its a 4runner, tundra, tacoma, FJ cruiser anything.

 

With that being said that is a very clean frame with whats shown in the pictures. I would brush the rust off hit it with this product called rust blocker then have the frame under coated.