There are several considerations in finding the right place for your dish. The first and most important is making sure that the dish will be able to see the satellite(s) you want it to see.
Use the channel charts to determine which satellites you want. Then go to a satellite angle calculator, pick the satellite, enter your location, and see what comes up. Here's how to read the results:
Determine the apparent compass direction by adjusting the azimuth by the magnetic declination factor as needed. Then go look to see whether there are any obstacles in that direction. If you plan to use a motorized dish, repeat this step for each direction you need.
Example: From Zip Code 80222, I want to see Galaxy 18 (123 W). When I plug that info into the satellite angle calculator, I get Azimuth 207.1. From the magnetic declination site, I know that I should subtract a little over 8 degrees from the azimuth to get my compass reading, which should be about 199 (19 degrees west of due south). The 0-declination line runs close to the Mississippi River. Viewers west of the line must subtract from the azimuth; east of the line, viewers must add to the azimuth to get the compass reading.
If there are any obstacles in the distance along this line of sight, the signal may be able to clear them. For example, at an elevation of 35 degrees, you can clear a 14-foot-high obstruction if the dish is just 20 feet from the base of it. Higher elevations require less horizontal distance to clear an obstacle; lower elevations require more distance. You might be able to use trigonometry to compute just how much of an obstruction you can clear.
If you want to install a motor to point a single dish at multiple satellites, verify that your chosen spot is not blocked in any of the directions you need.
Homeowners/Neighborhood Associations may not restrict you from erecting a dish less than one meter wide (about 39 inches). Even if a contract or covenant forbids them, the Federal Communication Commission's rules make those portions of the contract unenforceable. With rare exceptions for historic districts, all that an association can legally do is require you to place the antenna in the least obtrusive place that still allows for reception.
Condo/Apartment Residents may erect the same small (less than 39 inches) dish regardless of contracts to the contrary, but only in "exclusive use" areas such as private balconies. Residents may be restricted from attaching the dish to permanent structures. In such cases, tripods or weighted bases can be used to keep the dish steady.
Weather is one last consideration. It's much easier to wipe snow off a dish if you can reach it without a ladder.