This isn't advice, just what I'd do (and what I have done). Rent out existing property, re-mortgage to release as much as possible, which would probably be only 23,000 (85% LTV). Go interest-only on that mortgage, so your repayments should only be about 680 euro per month at 3.4%. Then buy new property using the savings that you presumably have (if you're looking for a house for 500k!) and the 23k from your re-mortgage. However, it means you will need 107k to put into your next house if you qualify for 80%. This includes 100k deposit, plus 30k stamp duty, minus 23k that you have from your existing property. Don't forget solicitors fees and moving costs too though! And tax on your rental income!