Hi Shuttergirl
From a BA's point of view....
If you're going to buy sight unseen, and don't have a trusted advocate or friend/relative who can check out the individual property to provide you with an unbiased point of view, consider hiring a BA for the negotiation and acquisition part only. This could at least provide you with peace of mind that you're not buying a lemon, or are somewhat swayed by the selling agent as to the "real" condition/position of the IP. Costs range, depending on the individual services offered, but you get the benefit of a thorough CMA as well as the BA's expertise/knowledge which isn't to be underestimated. Local knowledge is a must when buying in a new area- even if it's sourced via a third party.
Also remember to contact the local council to ensure no surrounding dvpt is likely to impede on your property or future infrastructure/roads upgrades etc are in the pipeline close by, that may affect noise etc.
The "subject to valuation" clause is fairly common with most contracts, though most lenders will usually end up valuing right on purchase price regardless. An independent valuation will yield a more thorough analysis and include recent comparable sales as well as specific data about the property, including replacement costs of the building alone. Valuations range in price from about $450+ but when you consider that you're looking at spending hundreds of thousands of dollars.....
If still anxious that all other boxes are ticked, but you need to see the property before making a final decision, consider signing subject to "final physical inspection satisfactory to the purchaser" or alternatively, depending on where you're buying, use the cooling off period to do this. Be aware, however, that if you do withdraw during the cooling off, you will forfeit 0.25%of the purchase price as penalty (here in NSW) to the vendor for taking the property off the market during this period.
Best of luck with it all- above all, be prepared, ask lots of questions of locals, investors who know the area, agents, PM's, council, even the local police station can be a wealth of information (they'll pretty much tell you where the "bad parts" of town are). If you want to spend the money and time to subscribe to a database such as RPData, then this is also another tool in the arsenal for locating information at your fingertips, such as comparable sales, sales histories, current stock on the market, on the market histories, aerial maps, owners information (eg Dept of Housing streets can put some buyers off) land sizes, street positioning etc. I wouldn't be without it as a BA, that's for sure.
Re: building/pest inspections. These are a must, as well as strata searches if buying units. If you are looking at a property that you may think has plumbing/electrical issues, it may also pay to get these inspected as well, as most building inspectors don't cover these areas and provide a visual inspection only.
Good luck with your search and hope you find a gem soon