[Pinski]

So my kegerator holds four cornies and I'd like to build up some "inventory" kegs to be on deck, take to events and such. The issue for me is I have no basement or extra fridge for storage.  I'm concerned about storing kegged beer in the garage during the summer months with warmer temperatures and fluctuations. Is this concern warranted?  Any advice? Thanks as always.

[euge]

I think the concern is warranted. Do you have a closet somewhere in the interior of the house that stays stable? I'm in the keep it on the cool side camp- mainly because it gets hot as hell here and it does have an effect.

[Pinski]

I could probably find some inhouse storage. Is there a "do not exceed" temperature I should try to avoid?

[euge]

YMMV but I'm not crazy about my homebrew spending too long in the upper 70's. It's why I don't brew a lot during the summer and choose the winter to ramp up the production.

[tygo]

I'd try to keep it below 70 if you're trying to keep it for any length of time. 

[gsandel]

you could build yourself a cold box out of 2x4s and insulation and mount a small air conditioner in it.....I actually saw on craigslist someone getting rid of 2 year old 5000 btu AC for $20.

[ibru]

Hey Pinski, you need some of Wease's friends to get your inventory in check....

[Pinski]

Can you imagine coming home to find 'friends' helping themselves to your kegerator uninvited?  Or worse filling and taking growlers?  I think I'd cr@p a bomber. I do share a lot of beer and friends are welcome to come over to visit and sample to their content. Folks seem to know that if they give me honest feedback and return rinsed bottles I'l keep bringing them pleasant surprises. 
As far as the inventory issue goes I'm not going to worry to much about having too many kegs in summer storage conditions for too long.  I believe Tom had some good advice a while back. Something along the lines of, "if you're worried about it going bad, have a party". That sound easier and more fun than building a cold box and closer to the truth, more likely to get buy in from the Brewmistress.