Hi guys,
I've recently been appointed as an agent of Solbank and of Halifax, though my experience is only in Fuerteventura in the Canaries, the agency is for whole of Spain. Happy to pass any information I have without obligation.
Halifax is a particularly good deal for UK expats, provided you can prove income. They will do up to 15 years interst only and for non-resident, they will lend up to 70% of loan to value (bank valuation) OR 80% of loan to cost (which is purchase price plus all taxes and costs) whichever is lower.
Rates are normally fixed for one year and relate to Euribor (either monthly or annual Euribor rates) and are typically Euribor +1% to Euribor + 1.25% for non-resident depending on LTV and customer credentials. Rates are cheaper for residents, but the acceptance criteria are different.
I think the best thing Halifax offers (for Brits) is a dedicated UK contact, and all documentation in English language.
Solbank, on the other hand, are a bit more flexible with customer forms. But both banks require what you would expect to provide in the UK, i.e.:
proof of income
letter from an accountant verifying your income
Experian credit report
and if you own other properties, a list of addresses, values, mortgages, income and lettings contracts.