Not just any guy with a printer is going to be a good marketer just like not every guy with a wrench is a mechanic. 

Next, I used a printer that has front and back capability to print off 750 specific messages with the address on the back of the paper.

Depending on your area, here is what I would do: research the areas you want to market in (im assuming for wholesaling), find the area that may have the most motivated sellers with homes that are most likely needing rehab in some way to add value (1985 homes and older), contact a reliable list broker, buy a list of 60,90,120 day LATE mortgage payment (this is different then default, NOD, NTS) this typically is .16 to .22 cents a lead, buy 1000, to save money get lined white ruler paper, hand write a note that you want to say to the mailers on a piece of copy paper using the lines of the ruler paper as a guide, then meticulously photo copy that note on the printer using the ruler paper as the printer paper so that you have 1000 nice lined paper print outs of your note that look like real hand written notes (do not hurry on this part, make sure it looks good, since this is your one chance at the mailing with that limited budget), then buy 1000 yellow greeting card sized envelopes from envelopes.com (canary yellow 4x5 ish), buy 1000 real stamps, HAND WRITE the first name of the late payment person on the top line of the letters, HAND write the mailing address on the envelopes, put a real stamp on it, then mail them off in batches of 250 a week if you are by your self or 500 if you have a partner (calls will come in and overload you).Get a way to track every call, return EVERY call even if its missed, go on all appointments, learn a ton, make something happen.This worked for me to get started once I had a budget. 

Can you not even afford a printer and nice clean white paper?

You can use the USPS and their Every Door Campaign to touch all doors in a route for about 16 cents, then add the postcard 6 x 9 created at a local printer, mine run me about 14 cents each, and you have a full 4 color 2 sided piece in the hands of the consumer in your target area for about 30 cents each.If you need a list, try a list broker, start small and see how good the list is.

So many people have computers and printers people expect the letter to be printed.On the dishonest part, I will let you decide. 

Personalized letters are huge and easier to do with the variable printing capabilities of many printers today.

I then made a hand written letter on printer paper and started coping it and writing in address and name.

Looked like printer's rollers were dirty.

Your business mail entry office can provide more information on discounts.Mailing From More Than One PlaceGenerally, you must hold a mailing permit and pay an annual mailing fee at every Post Office where you want to enter and pay for your mail.So if you want to keep mailing every year, there is an annual fee; if you want to mail from multiple POs (if you use two different printers and each enter their mail into a different PO) and so on.Rather than getting your own permit you can use the printer's permit for a fee and they can take care of everything.