So first of all, you need to know where you are. On the geostationary orbit there are 4 stable points dividing the orbit in quaters: 2 where an onbject is accelerated and 2 where it is de-accelerated.
The International Telecomunication Union is giving the O/O of GEO-Satellites "boxes" of 0,1 deg in which you have to keep your satellite.
So first you are in a box, where your satellite is accelerated:
Your Satellite is accelerated so (like in Hohman-Maneuvre) your Altitude is getting higher. So, you give negative delta V getting slightly under the GEO-Altitude. Because you are to low, your satellite will move respective to your box. That is okey, as long you are in your 0,1 deg box. While drifting in your box, your satellite is constantly accelerated. Because of the acceleration your orbit altitude rises. Idealy your Altitude reaches GEO-Altitude at the opposite end of your box. Still no maneuver needed. Your Satellite is still accelerated. Becoming higher and gettig above GEO. Now the Satellite drifts to the side of your box where you started. When reaching this end, you again give negative delta V and the whole process starts again.
For the other boxes, where your satellite is de-accelerate the process is reversed, so you will to give regulary positve delta V.
So, where are the constains?
Your delta V has to be so big, that a drift to the other end of the box and back takes 2 weeks. Exact number is dependig on the longitude of your box and have to be calculated for every box. But I hope this constrain is the answer to your question.