Like Andrew said, I definately would suggest checking several options. Most lenders differ from eachother one complete qualification requirements. Especially if you are looking to invest again before another two years.
Glad to help. Good Luck! - TonyB
From a lender's standpoint. They would take 75% of the rental income you get and then subtract your the mortgage payment. If this number is positive then you could say the property would be an asset to your new purchase. If the number is negative you could say that it is a liability. This is a very simplistic breakdown but it is pretty accurate. Keep in mind that just because it is considered a liability it doesn't mean that you won't qualify for a new loan.
Credit unions are great because they offer an alternative to banks and other mortgage lenders. Like most lenders, credit union loans are the great for some scenarios but not for others. I have heard the two year rule before but it is a bit strict. Try another bank or mortgage lender and you will probably have more luck.
You will be comparing all investment properties at about 75% of their income generated. Then the remaining balance will be counted toward your debt to income ratios and the lender will determine what risk is toward loaning you money toward a third investment.
It would be a good idea to run the numbers through one or two loan officers and see what they say.
It is a numbers game for sure.