- Your weight compared to the corpse's weight. If you're a big and burly fellow and the vic is petite, tossing him or her over your shoulder shouldn't be a problem. A bit messy, sure, but at least you'll only have to make one trip and dragging him or her across the lawn (or down to the basement) will be unnecessary since you can just lift and toss. If the reverse is the case, then perhaps chopping or otherwise segmenting the corpse will be needed before you can even move it.
- Time. If you've planned ahead, you can take all the time you have in order to get in a good corpse disposal. If, however, you've lost your cool and the party guests are in the next room just toss the unfortunate vic into a nearby trunk or armoire, do a quick mop up and hope for the best until you can do the job properly. Alternatively, hide the vic in plain sight. Assuming that alcohol has been consumed by said vic, then propping them up in a drunken pose will serve its purpose until later. Granted, this risks that you could get discovered, but being that most people at a party are highly unobservant, the chances of them even noticing ol' Jim is missing is very slim and won't happen until you've found the time.
- Method of homicide. For most methods of disposal, this isn't even an issue but if you have poisoned your victim, consuming the flesh is not recommended. Unless, of course, you wish to find yourself posthumously awarded with a Darwin.
- State of the victim before death. Again, usually not an issue, but consuming the flesh or exposing yourself unnecessarily to the blood products of someone that is HIV positive is not only unrecommended, but just plain dumb.
- Cleaning supplies. Yes, corpses are messy and it's your job to clean up (trust me, you don't want anyone else to). At minimum you should have: bleach, polyurethene gloves (or latex if you're not allergic), large garbage bags as well as either a mop or sponge. Since most households have these items (or, in a pinch, you can use gallon size freezer bags as gloves, but it's not a good idea if you don't have to) even an impulse killing can result in a quick clean-up.
My next entry will cover actual methods of disposal.