Nathan,
Welcome to BP! My full-time job is as a General Manager for a local building material supplier that delivers drywall throughout Central Iowa. This allows me to keep a pulse on the construction market because drywall is needed on almost all projects (commercial, multi-family and residential).
If you are looking for SFH Des Moines has opportunities for both appreciation and/or cash flow. I personally invest in SFH in Ames and it the inventory is very limited, sale price/rental rates are not great and appreciation has leveled out as well. Plus, on October 10 they are planning on putting a “6 month freeze” on the conversion of SFH to rental properties.
If you are looking for Multi Family I would stay away from Ames as the vacancy rates have spiked (estimates are 10% and could rise by end 2018 to 15-20%) because of out of state developers building large apartment complexes and A LOT more units are under construction currently. Multi-Family in DSM is very different because there are a lot of sub-markets.
Good luck and hope this helps!