Capacitors for MAX232
Just use the higher of the recommended values. For example, as per Table 9:




Capacitor
Value




C1
0.1 µF


C2, C3, C4
0.33 µF


Cbypass
0.33 µF




Typically, you'd want the lowest possible capacitance for the circuit to function - the lower, the cheaper. This is why they have a table with recommended values. However, using a higher capacitance will not hurt functionality (within reason). You might get a measurably slower start-up time, but the effect would be negligible.