1. Cash means F'all nowadays. In fact, dealers/sales associate generally get a small kick back from the finance company's so they actually prefer financing. Ohh and don't be surprised if you walk in with wads of cash and get sent back out to get a certified cheque. No intelligent dealer would gamble with possibly getting thousands of dollars of counterfeit cash.
2. Summer sale, fall sale, winter sale, spring sale....almost allllllways a sale going on. The only difference I'd keep my eye out for is financing specials. Sometimes at any random time of the year manufacturers will have 0% financing or deferred payment plans.
3. 100% agree! buy whenever you're ready and you're comfortable.