Hi Lillymay
1) Why do you want to keep the current house? How much is it worth? Is it a tracker mortgage?
If it's a tracker mortgage with one of the live banks, you may be able to sell the house and transfer it to the new place.
2) You should not borrow from the Credit Union. Their rates are much higher than mortgage rates.
3) Whether you remortgage Property 1 or take out a new mortgage on Property 2, will depend on the interest rate.
Assuming that the rates are not too different, then it is much simpler to take out a new mortgage on Property 2 which will be in your joint names. There are downsides to remortgaging Property 1 to fund the purchase of Property 2 e.g. they might want cross security.
4) It does not make sense to keep €20k savings. Effectively, you are borrowing at around 3.5% to put money on deposit at 0.5%. Unless you have a definite plan for the money in the next couple of years.
But you will have the rental income from Property 1 and you will have lower repayments because you have borrowed €20k less, so you will start building up your savings again.
You might wish to keep €10k to one side initially in case of unforeseen expenditure on the house. But when you have settled in and have no need for the money, pay it off the mortgage.
4) Make sure to take out a variable rate mortgage, so you can pay it off as quickly as possible without penalty. If you have a fixed rate mortgage, you will face penalties if you want to pay it off early.
Brendan