Hand Washing vs Car Wash Hose(High Pressure)

I have detailed and poilshed cars for years. Here is my opinions on what you ask.

Hand washing will always be better. Use a detergent made for car washing.
Using dish soap or laundry soap is a no-no.

There is nothing wrong with buffing your car out if needed. The thing here is you need to have experience. Yes you can swirl and virtually ruin clear coats and paint jobs. If you paint is in good shape and you just want to shine it up using a good orbital buffer and a good cleaner/polisher pad is the best and will eliminate the chance of swirls. I have had to clean swirled paint jobs up before... just did one actually that was soo bad.. metallic black... someone had no idea what they were doing. I fixed it. Doing it by hand is very time consuming, but usually does a satisfactory job. You however will always get a better shine from a machine buff/polish. Just ask the people that have seen my car !! ha ha. If you decide to buff/polish let me know through a p.m. and I can tell you some more pointers. High speed variable buffer/ polishers are only for very skilled people. Dont let anyone touch it with one unless you have seen their work before.

Hope that helps some.

-RPM