DIY playhouse kits are where it gets a little tricky. If you have a look around, you have seen some small house designs are quite complicated for sale. Most of these plans appear to be created by an experienced carpenter, who approached the project only as a scaled-down version of the actual houses they build familiar.
There is nothing wrong with having DIY playhouse kits built with the kind of strength and integrity, but whether the average DIY builders can take on a project like this is another story. If you know how to build a house, or know someone who does, the types of plans playhouse will work fine. If not, take some care to find a design project that is in the range of skills.
The good news is that DIY playhouse kits does not really need the details of the structure are the same as you would find in a real home. Here are a few places in the basic design where you can cut a few corners, and still has a fine playhouse for children. Floors, of some of the more complicated playhouse plans call for a 2×6 wood on all members of the floor joist. This is great for home and outdoor sheds, but a small playhouse can work well using 2x4s cheaper.