Most of the intimate vow renewal venues are outdoors and open to the public, so you could see them without having an official site visit. But I do know other intimate couples have manged to have a mini site visit with their co-ordinator.
do you live far away or within driving distance? imo I wouldn't spend much to make a special trip just to see the 4 intimate outdoor sites. they are exactly what you saw in everyone's wedding albums here. no extensive planning is required for intimate wedding.