I saw people converted NEMA 5-20 to NEMA 6-20. But the only A/C outlet I have in my garage is a NEMA 5-15. There is also no separate Panel in my garage. An Tesla approved electrician told me I needed a big project to add NEMA 14-50. It costs $3200. That's why I am thinking about whether there is inexpensive way to upgrade from the slow NEMA 5-15. My daily commute is less than 20 miles. So, I can technically live with a 5 mile/hour outlet. But the charging rate of a NEMA 6-20 would be perfect? But is it possible to get done inexpensively?