From my readings on this site it is clear that the main goal is to position yourself into using other peoples money to become a real estate mogul.

I'm just curious what strategy you would recommend if you came into $150,000 tax free cash?

For the sake of argument you have no debt to pay off other than a single mortgage?

Would you pay off that mortgage and use an equity line of credit to build off of?  Keep the mortgage as you are writing off interest?

Use it all for flipping?  Get into commercial properties by finding an apartment?

First you need to decide on what you want to do in real estate.

Choose a path by reading: http://www.biggerpockets.com/real-estate-investing

put it into an all cash deal, then refi it all out and put it into the next deal, and...

I have already read that.  I am just looking for advice on what more experienced investors would do.

My personal story is that I just purchased my first home the beginning of this year. I bought a duplex via a VA no money down loan. Out of pocket I had about $1000 for earnest money and inspections. My realtor wrote the offer such that I got money back on close. I was unable to receive all of the money back I would have gotten legally so I ended up buying my rate down 1 point. After that I got about $3,000 back in checks.

My current goal is to wait until I have been here a little over a year. This will establish the experience in property management required to use the VA loan to buy a 3 or 4 unit home.

I will then use my second tier entitlement VA loan to purchase said 3 or 4 unit with again no money down.

After I have lived there a year or so I intend on using an FHA 3.5% loan to purchase the single family home I want to live in for good. Obviously the goal is to ensure the rents from the first 2 homes will cover all 3 mortgages.

Once that was done I would bank enough of my cash flow to cover expenditures that may arise and then use the excess to pay down the homes 1 by 1.  Once I had enough equity I would take out an equity line of credit to start in on commercial investments.  I have a buddy who does 2-3 flips a year and I could buy in to his deals and have the money work for me until I had enough experience and then I figured I would trade the first 2 homes in for a small 18-30 unit apartment. 

However with the possibility of $150,000 cash at the start I am trying to broaden my view to other possible endeavors.  If I were to get the money today I would probably just invest with my buddy for awhile and take it from there.

Use the 150 for an operation account. Buy and sell as much as possible using the little or no down transactions it appears you've already worked before. And use the account for repairs and flipping. A business account to pay payroll and other operation costs will allow you to make more offers and maintain workers who'll become faster at their work and better quality to your standards. You'll soon find yourself growing faster and turning more properties. One by one is a secure way to go to flip houses but your using the money to operate on a grander scale your overall turnover costs timing and quantity will all leverage and maximize a return on a life changing scale.