Different size tire balancing/rotating

[370Z/28]

It is funny the things you SWEAR you will never do again, but you do it anyway. When I had my S2000, I swore that I would never have another 2 seater and I would never have another car that I couldn't rotate the tires. Well...my heart was WAY to into the deal on my Z when I looked down and saw the deep offset on the rear wheels and realized that they were wider than the front.

I'm coming up on 6k miles. What do y'all recommend for balancing or whatever the heck I can do to make these tires last as long as possible. I can't stand for tires to be the least bit out of balance. You guys know how anal I am.

[biggie]

Only good way to do it would be to rotate the tires from one side to the other every 7-10k miles. But paying someone to remove and swap tires with balance is going to be expensive.

Can just get the wheels balanced every (or every other) oil change, especially if you get a deal for free balancing.

I'm cheap, so I just let it go.