Does your house have gutters to keep the roof runoff away from the patio?
If you don't have any gutters, installing them can be relatively inexpensive and keep roof runoff away from the patio. That can reduce the water quite a bit, in my experience.
Otherwise, if the patio is sloped down towards the house, I cannot think of any cheap fixes. If what you have done is keeping the water out of the basement, you might want to keep an eye on it for the immediate future and determine your move once it decides to stop working.