If you want to make your own golems, craft wondrous items and craft magic arms and armor are the prerequisites to craft construct.
It's all going to come down to what you want to gain out of your crafting. If you have downtime allowing for a full 8 hour day of crafting you can accelerate the process to completing up to 2000gp towards the final product each day by increasing the DC by 5.
Do not be discouraged if you are mostly adventuring and not in towns for long. In a standard adventuring day you are able to craft for a maximum of 4 hours a day that attributes only 2 hours towards the end goal. Again, an increase of DC 5 will get this to 4 hours which allows for 500gp towards the final product. The crafting rules explain where this time is taken from. An hour or two combined between breakfast, lunch, dinner, bedtime to get the 4 hour cumulation.
Adventuring crafters will be able to do what's needed in twice the time it would take someone in town who's not rushing. Just make sure that if you do have time in town, you utilize it as best as possible so you can get the items you need.
Try planning out the order that you'd like to get the items you want to best use your time. Time management is your best friend since you can only work on one item at a time and if you start another before completing the first you lose everything you've invested into the first.
The problem with crafting constructs is that you might be required to do so in a workshop. How else did you shape the metal of the iron golem or whatever one you're making? Having a bag of holding would be key to have first since mages won't have the strength to carry around all the materials required. This shouldn't be hard as you can make those yourself with craft wondrous items.
It's entirely a viable build to become a crafter. There are many perks that will come of it, but just know that you will be using items to try to make up for the loss of a feat to a craft that could have been used to augment your skills.
