Hi Kiahjo,

There seem to be more and more affordable and reliable home test kits becoming available that test for formaldehyde and other chemicals.

http://prohousedr.com/DIYTestKits.htm offers a formaldehyde test kit for $50. They also offer a kit that tests for hidden mold and bacteria for $40. Unfortunately I can't see a test for VOCs.

For those in the UK http://www.homeaircheck.co.uk is an excellent company that offers testing for formaldehyde, other VOCs and mould, individually or as a package for a very reasonable £110.

I would say these types of test offer an affordable and increasingly reliable first step into identifying levels and sources of toxic exposure in your home. Far cheaper than having a company do an on-site home environmental survey only to find everything is fine.

I'll let you know if I come across any more reliable US-based test kits. Good luck!