I am trying to build a regression model using R where,
- price (continuous)
Age,accumulated kilometers,weight,horsepower,cylinder volume, tax (continuous)
Metallic color,ABS,Airbag,CD_Player,Power steering, Metallic_Rim (categorical - binary)
Color (Categorical - 5 levels)
Fuel Type (Categorical - 3 levels)
How can I detect the variables that should be used in my linear model in one step. I know that binary variables influence on response variable can be checked using T-test. How can I check which all of these variables(continous, categorigal-binary, categorical-multiple levels) influnece my response variable price in one step ??