If you really want your mail pieces to stand out, you can create a design on the front and use a specialty stamp.  

Cute stamp or professional?  

*im not sure of the cost of the loan we have a budget price on 3M.the plans with the engineering stamp are ready to be submitted to the city.* i think that every investor would have to be owners of companies that are stable and willing to invest on real state (multi-family) and their investment can be just his labor and materials paid by the loan or labor and material. 

Ask the HELOC lender you've found if 2015 taxes will be considered "validated" based on:1) IRS 4506-T request coming back with "not yet processed."2) Color copy of your stamped 2015 tax returns that you filed in person at the IRS.3) Copy of cashier's check for your tax bill that lines up with page 2 of your 2015 tax returns ("Amount You Owe") that is also stamped by the IRS.4) Bank statement showing the funds clearing your account that also lines up with the above two documents. 

Your house, your stamp, your call.

Also included were receipts, photos (date-stamped), and of course the check (less a few hundred dollars from violations/damages/etc). 

You need a good amount of blank space on the rear to have your stamp, their mailing address, and a bar code. 

My fiancé and I are looking to build a stamped concrete patio in our backyard as well as excavate the current patio.  

The best open rate is going to be on hand-addressed, first-class-stamped pieces.

Response rates aren't that high so you need a large sample size.2) Don't forget most people don't hear results until the 3rd-5th mailings so you need to stick to it3) Unless you're super small, you'll need software eventually or you'll ineffectively spend your time writing each letter individually, stamping, and mailing.