You need to be more specific. If it's for private use, is it a registered farm vehicle, recreational vehicle, or other vehicle exempt from classification as a commercial vehicle under FMCSR? In those cases, no, you don't. You might, however, be required to display "Not For Hire" on the sides of that vehicle.
If it is used for commercial purposes in interstate or intrastate commerce then yes you do have to cross scales at weight stations. You are also subject to the same laws of a typical commercial vehicle. If it's used as a private vehicle then no.
If the commercial vehicle requires a CDL to drive it, you do.
Yes, you do need a medical card for a commercial vehicle that weighs less than 26000lbs.
No, you can get a commercial policy for a commercial vehicle. If it's for a company you work for, I would make sure they had proper insurance before you drove the vehicle.
A Commercial drivers licence is the licence to drive any heavy weight vehicle. You do not need a parent in the vehicle with you when you drive on the streets. Although, you do need a parent present when you get your licence, and they have to sign the papers.
NOT necessarily. A company owned passenger car that is intended for the personal transportation of company employees would not need to be registered as a commercial vehicle. However, a vehicle used to transport goods would be considered a commercial vehicle. This is common in the logistics and transport industries.
If the vehicle is parked on a public street, you need a tag. If it is on private property you don't.
There's no logo requirement on a commercial vehicle. On a Class 8 tractor--a semi--you need the license plate (base plate) and either a DOT number or "not for hire." You can put "not for hire" on a truck that is not used in commerce, like the tractor that pulls a race team's trailer. Everyone else must have a DOT number. But as far as logos go, you don't need to have a logo on your truck.
You would need a commercial vehicle policy.
Commercial vehicles are defined as vehicles that are owned or registered to a company, instead of an individual. Additionally, heavy vehicles, vehicles used to carry hazardous substances, or vehicles able to carry more than 15 persons are also classified as 'commercial' even if privately owned. In order to drive a commercial vehicle, you need a commercial vehicle driver's licence. This imposes some extra responsibilities, such as informing your employer of certain convictions.
The title would be your receipt.
Yes. You need a Certificated Flight Instructor endorsement on your commercial airman's certificate.