I'd personally be inclined to have a lower exposure - mindful that the day usually comes when you have kids and may need to survive on one salary, even if you are gay - but at present:- 100k equity - allowing at least 25k for stamp duty and expenses, we'll say 75k down- 550k purchase price, let's assume you pay that (either asking price or a 25k discount on a 575k house or whatever- you'll need a 475k loan- that is 3.65x joint income, not too ridiculous and you should still be able to persuade someone to lend you that- it'll be about 2,200 pcm interest only, 2,900pcm repayment- suggest you do a monthly budget and work out whether you can afford this!- if you can now, think about future plans (family and career-wise)- be careful about opting for interest only, as it will of course need paying back at some point - may not be such an issue if you're confident of decent bonuses- with this level of exposure, you really should get a fixed rate to save yourself sleepless nightsThat's my take anyway