I'm a carpenter so I can do (and want to do) the interior repairs like the bathroom and kitchens renovations so I'd be paying for material costs only.

It's not just any amazement and any construction materials and any support staff, you want the A team, no matter what area.  

I've already completed the sections on Contracts and am working my way through Property Ownership.The only thing I wish I had is a downloadable copy of the materials so I don't have to be on my laptop to study.

Your time here will be well spent.You didn't mention a specific niche, so I took the liberty to add the below guides for flips, buy and hold as well as wholesaling from which you can pick one or all, while waiting for a local connection as an intern.http://www.biggerpockets.com/renewsblog/2013/02/22/buying-rental-property/ (how to buy a rental property)http://www.biggerpockets.com/renewsblog/2014/01/07/flipping-houses/ (step by step guide to flips)https://www.biggerpockets.com/renewsblog/2015/01/31/ultimate-beginners-guide-real-estate-wholesaling-2/ (Ultimate beginners guide to wholesaling)Now that you have made the move, below are some links that will help with the navigation of the site. http://www.biggerpockets.com/startherehttp://www.biggerpockets.com/meetSetting up Keyword AlertsHow to Use @Mentions on BiggerPocketshttps://www.biggerpockets.com/ruleshttps://www.biggerpockets.com/inviteshttps://www.udemy.com/biggerpockets-real-estate-investing-course/ (video with 64 lectures and approx 6hrs of material)https://www.biggerpockets.com/real-estate-investing (Ultimate beginner's guide to REI)Before your 1st purchase, please ensure you visit the below link for some tips.https://www.biggerpockets.com/renewsblog/2014/12/19/real-estate-investing-success-smart-tips/REI books suggested by BPershttps://www.biggerpockets.com/renewsblog/2015/11/13/7-real-estate-books-beginner-investors/ (7 absolute must read books for beginner REIs)http://www.biggerpockets.com/renewsblog/2013/04/14/best-real-estate-books/?

So far I have paid him in checks or some material from home depot.Is it enough to write down all payments/material provided to the contractor and have him sign and acknowledge that all this is received?

My biggest advice, never, ever let them get ahead of you on draws and I would advise until a level of trust is established that you purchase all the materials.  

Sometimes that means doing things myself, and a lot of the times it means coordinating all of the resources that need to come together to make things happen (people, money, materials, etc). 

I did keep and file electronically copies of all receipts as well as descriptions of all work done and materials required to complete the work.

I understand that the HOA is responsible for outdoor/external maintenance, while the owner is responsible for maintenance in the interior of the unit.I'm confused as outdoor outlets could technically belong to both so I'd appreciate it if someone with more experience regarding this type of thing could reach out with possible suggestions.TIA,Manuel

Things you must not doYou must not;i) Commit an act of bankruptcy; or fail to pay me on time any money you have to pay me under this contract; orii) Pay any repayment/s with a check, direct debit or other instrument that is subsequently dishonored by a bank; oriii) Fail to comply with any condition of this loan contract; oriv) Make any material false or misleading representation.6.