Once you've reviewed the guide and the UKBA website you'll be better placed to consider if your specific application will be straightforward or if there are some major complications.
Or it may be that neither of you can really dedicate the time needed to put the application together.
Remember though that you will both need to collect and put together all the needed documents.
Don't be shy to ask questions here.
If you both decide that you need an immigration advisor my advice would be to use a UK based resource.
Use an OISC (Office of the Immigration Services Commissioner) Immigration Advisor.
Their main webpage is
http://www.oisc.gov.uk