1. How many roaches do I need to start a colony?
The number will depend on a lot of factors such as the species you're considering and how soon you want to be able to start feeding out of the colony. Personally, I think with any live-bearing roach species you plan to use as a feeder, it's wise to start with a minimum of 50 to 100 roaches and ideally 200 to 500. That way, you can afford to lose a few roaches without severely setting back your colony's growth. Even with the best care, a colony of 50 to 100 can take several months to become established unless you happen to start with multiple adult pairs. Starting with less than 50 may very well take the colony at least half a year before it's ready to feed a small collection of reptiles.

2. What kind of roach should I try breeding?
The answer depends on what animals you would be feeding your roaches to and what kind of set-up you have those animals in. For example, lobster roaches are great if your animals consume a lot (a la bearded dragons). But lobsters can be a real pain to feed to your animals if you've got elaborate displays or large cages that the roach can easily hide in, never to be found and eaten. This may not be a problem if you know which of your animals are aggressive eaters and will come out from hiding to hunt down prey. However, don't bother using lobster roaches for your shy animals that only pop their heads out to catch whatever food walks by. Granted, my shy animals are usually my most vigilant ones that catch the lobsters as soon as they scurry out. But unless you have the patience to do any necessary corralling to ensure that the roaches get eaten, save the use of lobsters for your animals that have the sharpest hunting skills. (This may be a problem if your animals are used to being fed from a bowl.)

3. How long will it be before I can feed out of my colony?
Roach-breeding requires a certain time investment. Some species reproduce more quickly than others, whereas some appear to reproduce more quickly because they're more forgiving of husbandry errors. Rather than expecting quick results, you should be patient enough to wait upwards of half a year to a year. Larger species require several months before babies hit sexual maturity, then a few more months before you actually see more babies. In the scheme of breeding reptiles, this is really nothing, but it's a good idea to know what you're getting yourself into before you expect to see results.

4. Do you have a problem with escapees?
I've had lobster roach escapes happen for a few reasons. The first is that I've left the roaches in some of my animals' cages, assumed they would have gotten eaten overnight, only to be surprised when they scurry out from under the substrate when I'm cleaning cages. The second reason is that I have a few get flung out sometimes when I pack orders. The third type of escape I've had is from roaches that accidentally got thrown into the trash during cage cleanings, then climb their way out before I've taken out the trash.
I also have escapes happen from some roaches like B. lateralis and B. discoidalis that are able to get enough lift to fly out of their cage. Fortunately, it's only the males that are that eager to escape, which I consider to be natural mate-seeking behavior.

5. Which commercial gutload should I go with?
In my opinion, commercial gutloads are an easy solution for crickets because they eat anything indiscriminately. Roaches, on the other hand, are much smarter than crickets and know how to gutload themselves with different foods to maintain their optimal nutritional balance.¹ Keep in mind that we are not focusing on short-term gutload as with crickets, but long-term care for successful roach breeding. Most gutloads seem to concentrate on high protein and high calcium. However, contrary to popular belief, roaches do not grow as well on high protein diets and have no use for high calcium. Even orange heads (Eublaberus posticus), the one species I own that devours the most protein, will readily eat grains and vegetables. If you choose to use any commercial gutload, I recommend having it be merely one component of their diet. Offer them choices from all four food groups. I provide my roaches fresh sandwich bread, honey nut Cheerios, and kitty chow, but I don't grind them all together into one mixture since that would defeat the purpose of letting the roaches self-select their own diets. Carrots and orange slices are also favorites that never seem to get old. Leftover cornbread and sweet potatoes will also be eaten. Remember, variety is key.
¹For more information, see "Diet Balancing in the Cockroach Rhyparobia madera: Does Serotonin Regulate This?" by Randy W. Cohen. Journal of Insect Behavior 14:99-111, 2001.

6. Does this species have a defensive odor?
Essentially all roaches emit a defensive odor, with each species having its own distinct smell and some odors being stronger than others. It's similar to snake musk in that some people are very sensitive to noticing it, while others just get used to it.

7. Why aren't my roaches breeding?
Usually the people I hear who ask this aren't giving their roaches enough time (wait 1-2 months after your roaches becomes adults), clean their cages too frequently, or they check on their roaches too often. If you like to count your roaches, it's wise to stop the habit. Even if you cover up the sides of the cage with paper to give your roaches privacy, the 1-2 minutes of daily disturbance to look for babies is enough to prompt females to abort production. Note that this is usually only the case for oviviparous (live-bearing) roaches that drop egg cases when stressed.

8. Help! I have mites.
One thing I need to clarify is that there are different kinds of mites. Not all of them are parasitic, so don't worry about those tiny dust or grain mites possibly infecting your reptiles. Parasitic mites tend to be host-specific, meaning roach mites will only survive on certain roach species,² snake mites will only survive on snakes, etc. Roach mites are very easy to recognize because they are large and stay clustered around the roach's mouth. Usually the mites people encounter in their roach feeder colonies are dust or grain mites, which are much smaller, very uniform in size, and a white or peach color. Spring tails are another harmless small bug that are often mistaken for mites; they are oblong-shaped and characterized by their ability to jump.

I suspect substrates like peat moss and Bed-a-beast house dormant mite eggs. It either takes a dead cricket, wet cat/dog food, or some other decaying organic matter to trigger the mites. Food and flies seem to also be able to introduce mites to an otherwise clean colony. From my personal experience, maintaining a dry cage is a good way to prevent mites but not effective in getting rid of them. I've discovered the mites can only thrive in the top 1-2" of substrate. I managed to eradicate the mites by adding more substrate to smother them and then wiping the walls of the cage with a damp paper towel several times. Predatory mites (Hypoaspis miles) were also been extremely effective but only for smaller areas like tarantula cages.
²For more information, see "Food and water resources used by the Madagascan hissing-cockroach mite, Gromphadorholaelaps schaeferi" by J.A. Yoder and J.C. Barcelona Jr. Experimental & Applied Acarology 19:259-273, 1995.

9. How do I stop wing-biting in my colony?
This is normal for an overcrowded colony and despite popular opinion can occur with Blaptica dubia, any Blaberus, as well as Eublaberus. Many roaches are fine with overcrowding and will intentionally huddle together to conserve body water³. Overcrowding only becomes a problem when their numbers reduce each roach's chance of reaching a water source as often as it needs to. That's why I always recommend that people to provide vegetables or water crystal gel at least every other day--not because the species itself can't go for long periods of time without water, but because there's no guarantee every single roach in your colony will be able to reach the source of water before it runs out. You should try distributing the water or vegetables over as much surface area as possible, either by adding another dish or two or moving the colony to a bigger cage. This will help reduce the wingbiting in your colony. Insufficient protein is probably not the case or else they would be eating each other even when they're not freshly molted.
³For more information, see "Group influence on water conservation in the giant Madagascar hissing-cockroach, Gromphadorhina portentosa" by J.A. Yoder and N. C. Grojean. Physiological Entomology 22:79-82, 1997.