Hi there Mac and welcome to the forum
With regard to your query about married (or unmarried couples!) there is no such thing as a joint IVA, but you can propose mutual and interlocking IVA's which rely on each other, where one affordable contribution is made jointly and where both sets of creditors agree to receive the same dividend.
As to choosing an advisor - why not have a look at my blog which might give you some pointers and questions to ask when you have decided where to go.
Good luck in your search.
Regards, Melanie Giles, Insolvency Practitioner for over 20 years.
For further details contact me at
http://www.melaniegiles.com and view my IVA blog at:
http://melaniegiles.blogs.iva.co.uk