Wanting to buy but are not able to qualify for a bank mortgage at the moment.

You can "cash out" on as many properties that you qualify for.

However , I want to know if I can get involved in a specialised end like property appraisal - do i need to do be professionally qualified ?.  

It looks like they would qualify for the first time homeowners programs in NJ.http://www.njhousing.gov/dca/hmfa/homeownership/buyers/faqs/

If your monthly payment of your first house is higher because of the HELOC, your debt will be higher and the loan you will qualify for could be smaller.HELOC is a revolving account so if you max it out or spend more than a certain percent, it will lower your credit score.

@Robyn CoadyDid you end up finding a qualified real estate attorney in the Western MA area? 

Thx Rob I'm going to look into that I'm just concerned that my debt to income ratio won't allow me to qualify for another loan the bank gave me a hard time getting the loan I have now.

As long as you qualify to carry the debt you can keep buying houses with just 20-25% down until you can't carry the debt or you run out of the 10 mortgages.

You should then have a written agreement and if you receive a qualified offer that meets the terms of the agreement the seller would be obligated to pay your commission. 

After two years of history on my W2's I will need to use the income from the property to increase my DTI ratio in order to qualify for more future loans.