Depending on what equipment you purchase.....in my case, Stihl products, the carbs run me around 30-40 dollars and my time to replace them. I will spend more time running around and hopefully catching my dealer with extra kits,etc. and not always fixing the problem. Just take those carbs off and throw them away......or keep the aluminum for recycling.
More time than none...........it is the screen below the spark arrestor. Take that darn screen off and blow out the exhaust port, muffler and check the exhaust port for buildup. Replace fuel filters and air filters.
It is hard to consider taking care of lawn equipment like your automobile. Often we get real busy and the weeks fly by without maintenance. Take care of the equipment and it will take care of you.