Surrogacy with gender selection

Hello, I am new here looking for some advice.We have 2 girls and looking into pgd for gender selection but with surrogacy this time.I had multiple complications with my girls pregnancies and so decided to complete our family with surrogacy.I haven't found anybody on Google search with similar experience.I know it's going to be expensive so just looking for some advice.We live in California and I know it's done here but how different is that from just pgd?How much more expensive?Anybody done that before?