It is important to note however that dogs who are never, or seldom allowed indoors, are more likely to become bored - and as a result become disruptive (e.g. bark for attention) and/or destructive (e.g. dig up your newly- planted rose bush). This is because dogs associate their human family as their pack and can develop behavioural issues if they feel neglected as a consequence of being excluded from interacting with their pack.
Combination products can be cheaper than buying them separately. On the other hand, it can be difficult to compare the cost of combined products with separates, because it depends on the ingredients (for example, newer and potentially more effective flea treatments are more expensive than older ones) and the cost of supplying what's missing – there's no all-in-one that covers everything. And that's before you take the cost variations from retailer to retailer into account.