Stepping out onto a fresh, sealed deck changes your whole backyard routine. No more splinters under bare feet or watching the wood gray out in the sun. The actual staining and sealing takes a weekend of solid work if you do it yourself, or a couple of days if you hire it out. Late spring is the sweet spot to get this done, right before the heavy summer heat sets in and after the spring rains stop.
If you are hiring help, get at least three quotes from local pros so you know the going rate. A standard project usually runs about $900 for supplies and labor combined. Spreading that cost out over a few months keeps your cash flow steady while you get your outdoor space ready for the season.
Remember that the 0% intro window is a hard deadline, not free money. If you still have a balance left when those 18 months are up, deferred interest kicks in on the remaining amount and can get expensive fast. Pay it off before the clock runs out.