A good robotic pool cleaner keeps your water clear without you lifting a finger, and a solid one should easily last you four to five years. Don't fall for the hype of the newest spring releases. The technology doesn't change that much year-over-year, meaning last year's model does the exact same job for a lot less cash.
If you wait until late August when pool stores are desperate to clear out summer stock, you can find these machines marked down to around $1100. We can stretch that cost over a year and a half without paying a penny extra in interest.
Keep in mind that this promotional rate is not a permanent discount. If you still have a balance left on your card when the 18 months are up, the standard interest rate kicks in on whatever you still owe, which will quickly wipe out any clearance savings you got.