N.R.
We were born & raised in D.M. for 26 yrs., moved to Colo. Spgs, CO for 18 yrs., Minnetonka, MN for 10 yrs., Denver, CO 10 yrs., and back to D.M. past 4 yrs., so we have quite a lot to compare. Housing & cost of living is cheapest in D.M., by far. Winters are cold & snowy (except this year). You have to shovel every snow because it doesn't melt until Spring. Snow blowers are almost a necessity. Spring is out of this world with flowers, trees, green grass. Summer is great until July & August when it gets hot & bestly humid (think greenhouse). You have to mow at least once per week & spray for weeds. Compared to Colorado & Arizona, there are LOTS of weeds & many bugs (harmless). Mosquitoes are very bad in July & August. Your air conditioner will not stop running from June to mid-September.
Houses are much cheaper here than most everywhere else (except the Southern states). You should not have difficulty meeting your criteria and get a nice home for $200,000 or less.
Most any suburb in "West Des Moines" will be the best places to live and offer nice, affordable housing. Ankeny is nice and has grown tremendously, has lots of stores, shopping, etc., however, Ankeny has high property taxes and is probably more expensive to live than West Des Moines areas.
Any of these western suburbs are considered upscale and are most desirable for property values & good school districts: West Des Moines, Grimes, Johnston, Urbandale, Clive, Windsor Heights, Waukee. Waukee is probably the newest & fastest growing city. Grimes is where we live and borders rural area (i.e. cornfields, pastures, cows, horses, farms, etc.) which we like. It's a 5 minute drive to be in the country for nice weekend drives. All of these cities have their own parks, paved trails & bike paths. Remember anything you purchase near lots of trees, woods, ponds, streams, etc., are going to get LOTS of very pesky mosquitoes. Most suburbs do spray for them, and it helps, but certainly doesn't get rid of them.
We've always believed that buying resale gets you more for your money because someone else has already purchased curtain rods, curtains, hot tubs, swing sets, landscaping, put in sod, trees, etc.
I'm not sure about working with realtors versus home builders. Sorry, can't help there. I'm sure they do both here.
All west Des Moines cities are upscale and are good places to raise kids. We are in the Johnston School District which is considered one of the best in the state. Depending on where you live in Grimes, you have a choice of Johnston or Dallas Center-Grimes School District, which is also a good one.
Swimming indoors & outdoors is popular here, also fishing & boating. Winter is indoor & outdoor ice skating. Kids ride bikes, play at parks, roller skate indoors & outdoors, etc.
You may find the culture here to be different than Arizona. Iowa is a very conservative state. Compared to western states, dress is much more conservative year around. Iowa's population as a whole is considerably overweight compared to other parts of the country (I think it's the lack of exercise due to cold winters & humid summers). People are friendly and laid back. Friendly farmers like to congregate at the grocery stores, certain restaurants, during Iowa State Fair time (August). The pace here is not as slow as some parts of the country, but not as fast as many western states.
I hope this helps. You can contact me if you have more questions.