I had a 125 amp main panel and had the solar contractor upgrade it when installing my solar system a few years ago. I was out of physical space and electrical capacity, even with several half-size breakers. Because of my 2" conduit that ran to the transformer, the utility said the max panel upgrade I could do was 225 amps. They removed the existing wire to the transformer and then pulled in the largest wire in that conduit to help facilitate the panel upgrade (at no cost from the utility). The contractor charged $2,500 to replace the panel and all the breakers when installing the solar system, and it worked out very well. If you do upgrade the panel, you may want to consider adding a subpanel in the garage to help facilitate your EV charging in the future...